Surging Lumina....SOLVED!...NOPE UNSOLVED!

[skitchin]

Sorry I've not got the time to read through all the pages to see if this has been suggested - just had some surging occur in my GP and got her running like a dream now. My car was running real rough and actually died at times. But when I'd get on the road and open up it never missed a beat. I cleaned my MAF sensor, but noticed raw gas in the rubber housing of my intake. Had to get a new fuel pressure regulator and they also replaced my EGR solenoid.

[thikstik]

Skitchen, You should see quite a rise in mpg also.

[urbex]

Well today I installed all new AC spark plugs and AC wires. I'll see if that makes a difference, although it'll be hard to tell since it's only done it a few times in the last month now that it's getting colder out. The only days it did it recently were on warmer days...

 

On another note, I'm thinking it's probably not a fuel issue because all 6 plugs actually didn't look too bad. None of them looked rich/lean.

[skitchin]

Well today I installed all new AC spark plugs and AC wires. I'll see if that makes a difference, although it'll be hard to tell since it's only done it a few times in the last month now that it's getting colder out. The only days it did it recently were on warmer days...

 

On another note, I'm thinking it's probably not a fuel issue because all 6 plugs actually didn't look too bad. None of them looked rich/lean.

 

Cool, will be curious to hear back from ya on this. There ought to be some discernible change in doing all this.

[urbex]

Well I immediately noticed it idled smoother....but that doesn't mean shit because it's more than likely in my head... It's supposed to be a little warmer than average the next few days so we'll see how it does.

[Leo090]

Hey Urbex, you still have this problem? Mine went away since its fall and going into winter soon. I will probably have relapse in surging when the summer hits. I have heard before that its from leaking gaskets, but I have read people fixed their gaskets and the problem went away for only a few months. Its a hard situation. As always my advice is to just ignore it unless it interfere with safe operation of the vehicle.

[urbex]

Well it doesn't seem to be doing it nearly as much now that it's getting cold, so for all I know it might not do it again until next summer... So it's hard to tell if this will fix it. I'm keeping my fingers crossed. I do potentially have a tiny tiny leak in a gasket, but I'm not sure...so it's hard to say.

[urbex]

I have noticed that the car seems to idle smoother, and it doesn't "hiccup" at stop lights like it used to. I did drive a way the other day that has a slight incline that would make the car surge, and it didn't, but it could have been it was cold out...

[Leo090]

Hey Urbex, first of all you probably 100% have a gasket leak, but that's because of your engine make. If you do not see puddles of coolant on the floor, then you shouldn't worry.

 

From my own experience, coolant levels always drop mid winter, and my only educated guess is that extra coolant is used to run through your heater when you turn it on for the winter. That's why the level drops.

 

I've been following this posting of your hesitation for a while now, since I have the same issues during hot /wet summer days.

 

My only advice at this point, get a Japanese car. haha, if not, just deal with it until she starts stalling all the time. Think of it as a girlfriend, she will give you her problems, but at the end of the day she gets u from point A to B safetly, then your ok!

Do you get more issues when you put strain on your car, for instance turning on a heater or especially the Air Conditioner?

[urbex]

I did wonder about if straining the engine had anything to do with it...because it seemed like on days that was really hot when I had the A/C cranked up it would do it....but then again it was also hot out. Heater has no effect on it. So far it hasn't done it in months, but then again it is winter....

[Turbo Diesel]

I have a 1998 Lumina LS and I have had the same problem you mentioned for probably the last 2 or so years. When it first started happening it would only seem to do it in overdrive at around 60-70 mph with light throttle to maintain speed up slight grades. Over the past 2 years it seems to have just become worse with surging even in 3rd gear at 30 mph when trying to accelerate slowly (not even up a grade). It will not surge in 1st or 2nd gear only 3rd or overdrive at what now seems at any speed as long as its under any kind of light throttle.

 

My Lumina is equipped with a tachometer and I can actually watch the engine rpms increase as the engine "surges". The weather sometimes seems to have an effect on it. I have come to believe (just from my own insight), that when the air is thinner (lower Barometric pressure) the surging is worse. It will happen at more frequent intervals (2-3 seconds) and at higher intensities (250-300 rpm). When the air is denser (higher Barometric pressure) the surging is milder. It will happen at less frequent intervals (4-5 seconds) and at lower intensities (100-150 rpm). Now my logic behind this may be completely flawed, but I believe how the surging is effected can be attributed to some kind of air pressure difference. Also, as the grade of a hill increases, so does the intensity of the surging, as long as, the speed of the car is trying to be maintained up a grade. As well as having a tachometer, my Lumina is equipped with two Flowmaster Original 40 series mufflers, so the sound of the engine surging is even more apparent and that much more annoying.

 

The only code the pcm has ever thrown was due to carbon build-up in the intake manifold which blocked the recirculation of exhaust gas from the EGR valve. Fixing that problem had no effect on the situation and seems to be unconnected to the problem entirely. Since I have owned the car many things like the spark plugs, wires, fuel filter....etc that were mentioned above have been replaced but to no avail. I have cleaned the MAF once, but I have not cleaned the throttle body. Also, the TPS has been replaced (which was shorting out), but even that seems to not be connected to the problem. On top of all this, the transmission had to be completely overhauled right after 100000 miles when 2nd gear decided to go. Now the car is currently around 140000 miles. I have heard of vacuum lines having leaks the TCC not locking to cause the surging, but I have very limited knowledge on where the vacuum lines are and how a TCC operates for that matter. I have also heard of a bad fuel pump or catalytic converter can cause the surging. Both on my car are original equipment and I have noticed the car starts rougher when the gas in the tank is low.

 

I have searched for and read many threads in a wide range of forums to find some absolute answer, but none have ever shown up. Most of the threads are resolved with something like "I just cleaned off 'fill in blank' and now the problem is gone", or the problem hasn't been resolved at all. Also, the problem I'm experiencing seems to come in many different forms, but with "surging" of the engine being the interconnecting issue. This problem has been the most annoying thing I have ever experienced with a vehicle. I have never heard of this happening to any one else's car that I know personally and even my mechanic has no idea what it is. Just knowing every time I get into my vehicle that its not running at its full potential is really frustrating.

 

Sorry to high-jack your thread, but I thought you might like to know that your not the only one experiencing this problem.

 

If any of the knowledgeable members of this forum have any insight to this problem please reply.

 

 

***************************************************************************************************

 

I have a 1998 Lumina LS with the 3.1L V-6 engine and A/T. I have the EXACT SAME PROBLEMS, with strange engine surging issues.

 

No check engine light (SES) and no codes set. (I have a laptop with a OBDII program that even reads some live data.)

 

Intake manifold gaskets have been done, by me, with the (superior to OEM quality trash) Fel-Pro steel and silicone rubber gasket kit. Compression on all 6 cylinders are fine.

Intake and all EGR related ports have been thoroughly cleaned/scraped/de-carbonized/de-gunked.

I know for a fact that my IAC (tried a known good one in place of for a verification), my EGR (cleaned, and never had a problem with it anyhow), and TPS (brand new - replaced and I didn't need it) are all fine. Fuel pressure seems fine as well, and unless the pressure regulator ever starts leaking back through the vacuum line (which is the typical failure, and mine has not), then I have to assume that it is ok as well. New spark plugs and wires installed recently, as preventative when doing the LIM gaskets. Also installed new pushrods due to high wear, polished rocker arm sockets (where push rods ride), and cleaned all lifters out from the dreaded water and oil sludge caused by the infamously failed OEM intake gaskets. No notable change in performance, aside from I don't have to listen to the lifter clatter or "ticking" anymore - AMEN to that!

 

To make matters worse, I now have 2 "new" strange happenings that have recently surfaced (right after doing the intake manifold gaskets), and that I have been unable to figure out why... I've checked everything from electrical connections to vacuum lines, and everything seems to be in good order.

 

Now, when I start the engine, most of the time, but not always, the engine begins to "lope" (so to speak) at idle. It starts out minor and goes from bad to worse in a hurry, and eventually the engine stalls out. It always fires right back up. Anything off of idle, and it runs smooth and fine. RPM's fluctuate from about 450 to 1,500 when the thing is doing it's whacked out idle tripping out. The engine will also almost always die when you are coming to a stop sign or light. Again, it restarts, and you whack the throttle and off you go.

 

All I can say now is... WTF is wrong with this thing?!?!

 

Last but not least... the cooling fans don't seem to come on like they should. I've bled the godforsaken cooling system umpteen million times, to be sure that no air is trapped in the cooling system. I know the water pump is circulating coolant fine. I know the thermostat is working, and not stuck shut. I know the fan motors are good (tested them) and I know the fuses and relays are good.

So, that leaves only the ECT sensor/switch. (Engine Coolant Temp). Well, I tested that, and according to all of the tests, it's supposed to be ok. Regardless, I really have my doubts on that though.

If I unplug it, both of the cooling fans come on, and then the right fan shuts off, but the left fan continues to run indefinitely. My ECT has 3 wire connector. A black, a yellow, and a green wire. I know many of these 3.1L's have a 2-wire ECT rather than a 3-wire. Not sure what the 3rd wire (green) is for? I do know that this particular ECT controls both the fans AND the coolant temp gauge in the dash, so I'm betting that probably the green wire has to do with the gauge.

 

Aargh... F-this car... I've begun spending so much time and money on it, it makes me sick.

 

Anyone that can help me... PLEASE do so! I will be eternally grateful.

Heck, I'm even willing to send you some money if your suggestions to actual solution(s) fix my P.O.S. car - Seriously!

 

I can deal with the surging problem (I have for many years now)... but the funked up idle and the cooling fans not coming on when they should... Engine coolant temps get up to about 226 degrees F and the damned fans don't come on unless I unplug the ECT sensor.

I just can't let these problems go, they've gotta get fixed - and soon!

~AJ

Edited May 6, 2012 by Turbo Diesel
Forgot some pertinent information

[urbex]

Hmmm... I did forget to update this.

 

YES! I believe the problem is solved! It's been hot (around 90 degrees) and rainy, both of which would be conditions for it to surge. It hasn't done it once since I replaced the spark plug wires, so I'm guessing at 13 years old and 160k miles their time was up. There's one stretch on Dort Hwy where it would ALWAYS surge if it was hot or rainy, and I've driven it a couple times just to see and it hasn't done it. So it really looks like that was the culprit!

[Garrett Powered]

***************************************************************************************************

 

I have a 1998 Lumina LS with the 3.1L V-6 engine and A/T. I have the EXACT SAME PROBLEMS, with strange engine surging issues.

 

No check engine light (SES) and no codes set. (I have a laptop with a OBDII program that even reads some live data.)

 

Intake manifold gaskets have been done, by me, with the (superior to OEM quality trash) Fel-Pro steel and silicone rubber gasket kit. Compression on all 6 cylinders are fine.

Intake and all EGR related ports have been thoroughly cleaned/scraped/de-carbonized/de-gunked.

I know for a fact that my IAC (tried a known good one in place of for a verification), my EGR (cleaned, and never had a problem with it anyhow), and TPS (brand new - replaced and I didn't need it) are all fine. Fuel pressure seems fine as well, and unless the pressure regulator ever starts leaking back through the vacuum line (which is the typical failure, and mine has not), then I have to assume that it is ok as well. New spark plugs and wires installed recently, as preventative when doing the LIM gaskets. Also installed new pushrods due to high wear, polished rocker arm sockets (where push rods ride), and cleaned all lifters out from the dreaded water and oil sludge caused by the infamously failed OEM intake gaskets. No notable change in performance, aside from I don't have to listen to the lifter clatter or "ticking" anymore - AMEN to that!

 

To make matters worse, I now have 2 "new" strange happenings that have recently surfaced (right after doing the intake manifold gaskets), and that I have been unable to figure out why... I've checked everything from electrical connections to vacuum lines, and everything seems to be in good order.

 

Now, when I start the engine, most of the time, but not always, the engine begins to "lope" (so to speak) at idle. It starts out minor and goes from bad to worse in a hurry, and eventually the engine stalls out. It always fires right back up. Anything off of idle, and it runs smooth and fine. RPM's fluctuate from about 450 to 1,500 when the thing is doing it's whacked out idle tripping out. The engine will also almost always die when you are coming to a stop sign or light. Again, it restarts, and you whack the throttle and off you go.

 

All I can say now is... WTF is wrong with this thing?!?!

 

Last but not least... the cooling fans don't seem to come on like they should. I've bled the godforsaken cooling system umpteen million times, to be sure that no air is trapped in the cooling system. I know the water pump is circulating coolant fine. I know the thermostat is working, and not stuck shut. I know the fan motors are good (tested them) and I know the fuses and relays are good.

So, that leaves only the ECT sensor/switch. (Engine Coolant Temp). Well, I tested that, and according to all of the tests, it's supposed to be ok. Regardless, I really have my doubts on that though.

If I unplug it, both of the cooling fans come on, and then the right fan shuts off, but the left fan continues to run indefinitely. My ECT has 3 wire connector. A black, a yellow, and a green wire. I know many of these 3.1L's have a 2-wire ECT rather than a 3-wire. Not sure what the 3rd wire (green) is for? I do know that this particular ECT controls both the fans AND the coolant temp gauge in the dash, so I'm betting that probably the green wire has to do with the gauge.

 

Aargh... F-this car... I've begun spending so much time and money on it, it makes me sick.

 

Anyone that can help me... PLEASE do so! I will be eternally grateful.

Heck, I'm even willing to send you some money if your suggestions to actual solution(s) fix my P.O.S. car - Seriously!

 

I can deal with the surging problem (I have for many years now)... but the funked up idle and the cooling fans not coming on when they should... Engine coolant temps get up to about 226 degrees F and the damned fans don't come on unless I unplug the ECT sensor.

I just can't let these problems go, they've gotta get fixed - and soon!

~AJ

 

 

sounds like what mine did really bad like that before I tuned the throttle follower.

[Turbo Diesel]

Hmmm... I did forget to update this.

 

YES! I believe the problem is solved! It's been hot (around 90 degrees) and rainy, both of which would be conditions for it to surge. It hasn't done it once since I replaced the spark plug wires, so I'm guessing at 13 years old and 160k miles their time was up. There's one stretch on Dort Hwy where it would ALWAYS surge if it was hot or rainy, and I've driven it a couple times just to see and it hasn't done it. So it really looks like that was the culprit!

 

Huh... Well, glad to hear it was such a simple fix for your vehicle. I'm surprised you left wires on your car for so long, but then again, most people run them well beyond their years. LOL I sure wish that's all that's wrong with my car. New plugs and wires haven't changed anything with my vehicle. I've heard that the coil packs and ignition module can cause wierd issues. I think the next thing I'm going to try is to swap some known good coils and module, and see what that does for me. The search goes on...

[skitchin]

***************************************************************************************************

 

I have a 1998 Lumina LS with the 3.1L V-6 engine and A/T. I have the EXACT SAME PROBLEMS, with strange engine surging issues.

 

No check engine light (SES) and no codes set. (I have a laptop with a OBDII program that even reads some live data.)

 

Intake manifold gaskets have been done, by me, with the (superior to OEM quality trash) Fel-Pro steel and silicone rubber gasket kit. Compression on all 6 cylinders are fine.

Intake and all EGR related ports have been thoroughly cleaned/scraped/de-carbonized/de-gunked.

I know for a fact that my IAC (tried a known good one in place of for a verification), my EGR (cleaned, and never had a problem with it anyhow), and TPS (brand new - replaced and I didn't need it) are all fine. Fuel pressure seems fine as well, and unless the pressure regulator ever starts leaking back through the vacuum line (which is the typical failure, and mine has not), then I have to assume that it is ok as well. New spark plugs and wires installed recently, as preventative when doing the LIM gaskets. Also installed new pushrods due to high wear, polished rocker arm sockets (where push rods ride), and cleaned all lifters out from the dreaded water and oil sludge caused by the infamously failed OEM intake gaskets. No notable change in performance, aside from I don't have to listen to the lifter clatter or "ticking" anymore - AMEN to that!

 

To make matters worse, I now have 2 "new" strange happenings that have recently surfaced (right after doing the intake manifold gaskets), and that I have been unable to figure out why... I've checked everything from electrical connections to vacuum lines, and everything seems to be in good order.

 

Now, when I start the engine, most of the time, but not always, the engine begins to "lope" (so to speak) at idle. It starts out minor and goes from bad to worse in a hurry, and eventually the engine stalls out. It always fires right back up. Anything off of idle, and it runs smooth and fine. RPM's fluctuate from about 450 to 1,500 when the thing is doing it's whacked out idle tripping out. The engine will also almost always die when you are coming to a stop sign or light. Again, it restarts, and you whack the throttle and off you go.

 

All I can say now is... WTF is wrong with this thing?!?!

 

Last but not least... the cooling fans don't seem to come on like they should. I've bled the godforsaken cooling system umpteen million times, to be sure that no air is trapped in the cooling system. I know the water pump is circulating coolant fine. I know the thermostat is working, and not stuck shut. I know the fan motors are good (tested them) and I know the fuses and relays are good.

So, that leaves only the ECT sensor/switch. (Engine Coolant Temp). Well, I tested that, and according to all of the tests, it's supposed to be ok. Regardless, I really have my doubts on that though.

If I unplug it, both of the cooling fans come on, and then the right fan shuts off, but the left fan continues to run indefinitely. My ECT has 3 wire connector. A black, a yellow, and a green wire. I know many of these 3.1L's have a 2-wire ECT rather than a 3-wire. Not sure what the 3rd wire (green) is for? I do know that this particular ECT controls both the fans AND the coolant temp gauge in the dash, so I'm betting that probably the green wire has to do with the gauge.

 

Aargh... F-this car... I've begun spending so much time and money on it, it makes me sick.

 

Anyone that can help me... PLEASE do so! I will be eternally grateful.

Heck, I'm even willing to send you some money if your suggestions to actual solution(s) fix my P.O.S. car - Seriously!

 

I can deal with the surging problem (I have for many years now)... but the funked up idle and the cooling fans not coming on when they should... Engine coolant temps get up to about 226 degrees F and the damned fans don't come on unless I unplug the ECT sensor.

I just can't let these problems go, they've gotta get fixed - and soon!

~AJ

 

Poor idling and dying at stoplight sounds like fuel pressure regulator or the fuel pressure itself. Beyond that, ignition coils or a sudden drop in power(amperage or voltage, ie bad alternator or connection) could be the cause.

 

Also dealing with cooling issues myself - fans are programmed to kick in higher than they should, I plan on reprogramming this, but I'm not convinced on lower temp thermostats.

Edited May 8, 2012 by skitchin

[Turbo Diesel]

sounds like what mine did really bad like that before I tuned the throttle follower.

 

The throttle follower? What the heck is that?

[Turbo Diesel]

Yeah, I hear you on the thermostat thing. I'm a fan of sticking with what the OEM t-stat temp is, unless you start modding the engine and need to run a cooler temp. Most engines run best at warmer temps (around 200 deg F).

 

As for the stall out... I do still have to check my fuel pressure and my regulator, but I really don't think that's it. Reason being, this problem just showed up right AFTER I just replaced the LIM gaskets. Regardless, I will still be testing fuel pressure out again once I get some time. As I recall, I checked it last summer back when I installed a new TPS when I was trying to get rid of a higher RPM surging problem that I never did get to the bottom of. Fuel pressure at that time was fine, as was the regulator.

 

Furthermore, why is it that if I pull the PCV valve from the front valve cover, and let it hang by the tube that runs to the intake and rear valve cover, the engine idle "loping" smooths right out and idles fine? That's what really boggles my mind about this problem. Basically I'm creating a small vacuum leak into the intake and the idling problem vanishes!? Now to me, that's fricken wierd!

 

Tested alternator and battery. No problems there.

 

I've read and heard that the coil packs and the ign module can be troublesome on these engines. I have some known good used ones that I plan to swap pretty soon, to see if it makes any difference. Unfortunately, I often don't have the time to work on my vehicle until the weekend.

[White93z34]

Topic back open, thread cleaned up.

 

I don't know what went on elsewhere on the internet but leave it at the door. There is some real good information here, lets keep it coming.

 

thanks.

Edited May 8, 2012 by White93z34
topic reopened

[skitchin]

Yeah, I hear you on the thermostat thing. I'm a fan of sticking with what the OEM t-stat temp is, unless you start modding the engine and need to run a cooler temp. Most engines run best at warmer temps (around 200 deg F).

 

As for the stall out... I do still have to check my fuel pressure and my regulator, but I really don't think that's it. Reason being, this problem just showed up right AFTER I just replaced the LIM gaskets. Regardless, I will still be testing fuel pressure out again once I get some time. As I recall, I checked it last summer back when I installed a new TPS when I was trying to get rid of a higher RPM surging problem that I never did get to the bottom of. Fuel pressure at that time was fine, as was the regulator.

 

Furthermore, why is it that if I pull the PCV valve from the front valve cover, and let it hang by the tube that runs to the intake and rear valve cover, the engine idle "loping" smooths right out and idles fine? That's what really boggles my mind about this problem. Basically I'm creating a small vacuum leak into the intake and the idling problem vanishes!? Now to me, that's fricken wierd!

 

Tested alternator and battery. No problems there.

 

I've read and heard that the coil packs and the ign module can be troublesome on these engines. I have some known good used ones that I plan to swap pretty soon, to see if it makes any difference. Unfortunately, I often don't have the time to work on my vehicle until the weekend.

 

IMO, sounds like you're running rich. A vacuum leak should lean out your A/F ratios, but if you're running rich to start with then the leaner ratio would actually help. Fuel pressure regulator is my best guess at this point.

 

Edit: Something else you might check, pull your air intake and see if there's any gas burping out of the throttle body.

Edited May 9, 2012 by skitchin

[chevylover95]

Does anyone know if the 1995 chevy lumina 3.1L has a port for a diagnostic machine ?

[Garrett Powered]

Yeah, I hear you on the thermostat thing. I'm a fan of sticking with what the OEM t-stat temp is, unless you start modding the engine and need to run a cooler temp. Most engines run best at warmer temps (around 200 deg F).

 

As for the stall out... I do still have to check my fuel pressure and my regulator, but I really don't think that's it. Reason being, this problem just showed up right AFTER I just replaced the LIM gaskets. Regardless, I will still be testing fuel pressure out again once I get some time. As I recall, I checked it last summer back when I installed a new TPS when I was trying to get rid of a higher RPM surging problem that I never did get to the bottom of. Fuel pressure at that time was fine, as was the regulator.

 

Furthermore, why is it that if I pull the PCV valve from the front valve cover, and let it hang by the tube that runs to the intake and rear valve cover, the engine idle "loping" smooths right out and idles fine? That's what really boggles my mind about this problem. Basically I'm creating a small vacuum leak into the intake and the idling problem vanishes!? Now to me, that's fricken wierd!

 

Tested alternator and battery. No problems there.

 

I've read and heard that the coil packs and the ign module can be troublesome on these engines. I have some known good used ones that I plan to swap pretty soon, to see if it makes any difference. Unfortunately, I often don't have the time to work on my vehicle until the weekend.

 

 

what do you think tuning the throttle follower does? it follows the throttle position giving it more air so when its shut, the engine still has air to breathe. you can tune a graph of points within the chip that control or smooth the idle.

[animuldriver]

Ok...so today I was heading home from work, the cruise was set at 60mph, and for some reason every couple of seconds the car would almost surge, kind of like I was tapping the gas pedal. Let me also say that it had down poured earlier in the day, so the roads were wet.<br><br>

<br><br>

Now for some background info. This started happening to me about a year ago or so. I'd notice anywhere typically from 50+ mph it would do this occasional, but mostly when wet. I had a few times on dry occasions it would do that, but most of the time it was when the roads were wet or after a car wash. Sometimes it would do it while accelerating, other times at constant you'd speeds. Someone suggested I replace the speed sensor behind the right wheel, so I did that...nothing. I did notice the PCM was partially uncovered, so I snapped the lid back down and it hadn't done it since...but it was also started to get to be winter, so there wasn't as much water on the roads. Also, no check engine lights, and I plugged my scanner in and it doesn't find anything wrong.<br><br>

<br><br>

Beings that water seems to have an effect, I would almost think it's something electrical. I did find at one time a TSB (#05-06-04-058) that says to replace the TPS sensor...and I've seen another TSB saying to replace the MAF sensor. The TSB about the TPS sensor says specifically that no lights will be set..so that looks plausible, but I'm still thinking it seems electrical...? And I have no tach, so I can't tell if the RPMs are jumping when it's doing it or not.<br><br>

<br><br>

Does anyone have any ideas? Or has had this happen to them? I recently cleaned the throttle body, EGR area tubes thingy, and the MAF. Everything in the induction system looks good....and I was hoping not to buy things that I don't need (beng a broke college kid) unless I have to....<br><br>

<br><br>

Thanks guys!<br><br>

<br><br>

(Oh, the obvious...3.1 engine, 4T60E transmission)

 

My lumina was doing the same thing till I sucked it up and changed my throttle position sensor. Had no codes but was acting up so I changed it for kicks and eurika!!!!!

[Fellowmann20]

Well, after 2 years and 30,000 miles since I posted about my car's surging issue in this thread, I have finally found something that will fix/correct my problem.

 

Back in the summer, after believing for a long time that the surging problem was related to the engine itself or its supporting systems, I came to the conclusion that it wasn't engine related at all. I learned that on these particular GM transmissions (4T60E) that the torque converter is not active until 3rd or 4th gear (overdrive) is selected. In my case, the surging is not present unless the car is in 3rd or 4th gear, so I think its safe to say that if the problem was engine related it would be present no matter what gear the transmission was in. This led me to believe that the surging issue was related to the transmission and, particularly, the torque converter itself.

 

The transmission in my car was overhauled at 100,000 miles. A new torque converter was installed and, of course, new transmission fluid was added. To this day I do not know what type of fluid was added, but I asssumed that the proper fluid was put back into the transmission. Based on this, I believe the problem is attributed to either a faulty torque converter, the wrong or bad transmission fluid, a bad solenoid becoming stuck, or passages/valves within the transmission becoming clogged or stuck.

 

On this assumption, I began searching online specifically for bad torque converter symptoms. Within a few minutes I stumbled apon a Ford F-150 forum where someone was experiencing a transmission shudder with their pickup truck. Someone else in the thread recommended they try using Dr. Tranny's Shudder Fix by Lubegard. The owner of the truck reported that he bought some and used it and it cured the transmission shudder. So I researched the product online and found that many other people have had success with the product. I thought I would try it because it was only $7 and after trying to fix the problem for over 4 years I was willing to try anything. To add to that, my car is 15 years old and has over 170,000 miles so its a test vehicle for anything that may have a chance of fixing it.

 

Anyway, Dr. Tranny's Shudder Fix is a 2 oz tube of what looks like transmission fluid that you pour directly into the transmission check tube while the engine is off. Upon start up and driving the car I immediately noticed something was different. The transmission shifted a lot smoother and after driving it about a mile the surging in 3rd gear was barely present and there was no surging in 4th gear. While driving throughout the next week, I found that I could now drive up a relatively steep incline on the Interstate at 65-70 mph with the torque converter in a solid lock up and no surging present at all (IT WAS GOOD! ). I could also accelerate slowly driving around town without the engine surge in 3rd or 4th gear. Once, it was nearly impossible to affectively use either gear to slowly accelerate to the desired travel speed but now it was cured. About a week later I also put 5 oz of Lubegard ATF Protectant for better long-term performance of the transmission.

 

Now this is not a sales pitch for Lubegard products, but I tried their product and it fixed/corrected my problem. I say corrected because I have noticed since the temperatures started dropping this last week that the surging has returned ever so slightly until the transmission warms up. Right now I attribute this to the lower temperatures and not the performance of the Lubegard product itself, but I could be wrong. Anyway, I may add another 2 oz tube of the shudder fix fluid and see what happens.

 

In conclusion, I am glad I finally found something that has corrected the surging problem and wanted to share with this forum so others could find out. However, I would still like to know other's opinions or insights on the actual problem itself. Specifically, if anyone knows if it is the torque converter, transmission fluid, a solenoid , or a stuck/clogged valve is the actual problem?

Edited October 23, 2013 by Fellowmann20

[RobertISaar]

you haven't corrected the problem, only masked it.

 

it could be anything that you listed, they're all known for failing at various rates.

[urbex]

I'd be leery of buying any lube from a "Dr. Tranny".