Jhobuu Posted December 16, 2004 Report Share Posted December 16, 2004 Apologies in advance for what may be a long post. First, I want to say that I have been reading the back posts, both to learn more about my car, and to possibly find an answer without having to bother anyone. I just want to say that from all that reading, it seems like this is a great place, with a lot of knowledge to be found, and people who really love this style of car. The reason for this post is I'm at my wits end here trying to find a solution for a problem with my '89 Grand Prix. I've got the 2.8 with a manual trans, and it seems like the enine is slowly losing power. I just got the car back from my mother, who had it for a year or so, and it is just not the same. It used to respond really well, decent power, and great mileage. Now all that is down the tube. The car shudders in the beginning of every gear, like I am shifting too soon, and I can't even use 5th gear anymore, due to the shaking and complete lack of power. I have to take the rpms up to almost 3K before shifting, or it will shake like a wet dog when I move up a gear. The engine seems to run fine at idle, but has no power in any gear. I took it to a mechanic to get the radiator replaced, and a new heater core installed, (apparently there was a mishap with some kind of additive, and they both were blocked up) and he told me to check the fuel pump. I took a fuel pressure reading at the rail, and with the key on, engine off, I had no pressure at all. I read in the haynes manual that there should be around 40 psi from that reading. With the engine running, the reading was around 35 psi, still too low, I think. So I replaced the fuel pump. No change in performance. I haven't taken another pressure reading, since the guage that I borrowed isn't available anymore. Also, the fuel mileage is around half of what it was 2 years ago. Maybe 13 miles to the gallon. I read an article here about ethanol fuel causing the fuel injectors to basically rot out, and since I live in the midwest, there really isn't much of an option to get non-ethanol fuel. Would the engine still run well in neutral with that kind of an injector problem? I'm about to get another 2.8 from a friend that I can gut for parts, or even swap in, if that is necessary, but that is a ways in the future, and I don't want to put off repairing this until the thing dies on me, and I don't have transportation until I can get that other engine. Thanks in advance for any advice or help anyome can give. Quote Link to comment Share on other sites More sharing options...
digitaloutsider Posted December 16, 2004 Report Share Posted December 16, 2004 Have you tried the obvious thing of changing the fuel filter? Quote Link to comment Share on other sites More sharing options...
WhiteMonteZZZ Posted December 16, 2004 Report Share Posted December 16, 2004 Have you tried the obvious thing of changing the fuel filter? :withstupid: Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted December 16, 2004 Report Share Posted December 16, 2004 By ethanol do you mean you're running E85? or regular gasoline? Quote Link to comment Share on other sites More sharing options...
Jhobuu Posted December 16, 2004 Author Report Share Posted December 16, 2004 Fuel filter was changed along with the pump... Sorry, kinda tired. Yeah, pump gas, 86 oct unleaded. Every station here puts ethanol in, though. Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted December 16, 2004 Report Share Posted December 16, 2004 yeah, most gasoline is ~10-15% ethanol anyway. Quote Link to comment Share on other sites More sharing options...
digitaloutsider Posted December 16, 2004 Report Share Posted December 16, 2004 Ohhh you have that shitty 86 octane shit there in NM. I know.. i was stumped when I first came there and saw it. Where was the car driven previously? Quote Link to comment Share on other sites More sharing options...
sonyman87 Posted December 16, 2004 Report Share Posted December 16, 2004 Car stumbling.. sounds like fouled plugs.. have you checked the airfilter also? what maintnece has been performed? does the car sound like marbles from underneath? i got lots of questions.. so i will leave you to fill these out first Quote Link to comment Share on other sites More sharing options...
WhiteOut Posted December 16, 2004 Report Share Posted December 16, 2004 yeah, most gasoline is ~10-15% ethanol anyway. Actually no. Any gasoline with more than 5% ethanol must be labled as such. The only stations I've seen selling an ethanol blend are Speedway (10$ EtOH), or those selling the E85. And to the earlier comment about ethanol eating away at fuel injectors. Thats total crap. Ethanol is a horrible solvent when it comes to plastics. Ethanol is liqour (as in drinking alcohol) for God sakes, it comes in plastic bottles at the store. Its pH neutral as well so you don't have to worry about it being "acidic" in any way. The only thing that might dissolve in it is adhesives, pigments (i.e paint), and some resins. Quote Link to comment Share on other sites More sharing options...
Jcrow Posted December 16, 2004 Report Share Posted December 16, 2004 I vote for spark plugs! the clutch dosen't slip, does it? Quote Link to comment Share on other sites More sharing options...
Jhobuu Posted December 16, 2004 Author Report Share Posted December 16, 2004 The plugs are fine... New actually, and I don't think that I EVER want to go through getting the back 3 in again. The air filter is kinda old, but still clean. As far as the clutch goes, I don't think that it is slipping. I've never had one slip on me, so I wouldn't really know, but once the gear is engaged, and up to around 2300 rpm, it's fine. I do know that the pedal seems a little tight, though. I have to really press it into the floor to get it to disengage, and once I lift it off the floor, even a fraction of an inch, the clutch is kicking in. The car was driven only in NM, as far as I know. As far as maintenance goes, oil changes are up to date, trans was serviced a few months back, everything is lubed. Had the ECM cleared when the rad. was replaced. I know that the serp. belt is getting close to needing a replacement, but other than that, everything is fine, as far as I know. Marbles underneath? Don't quite understand. Quote Link to comment Share on other sites More sharing options...
Jcrow Posted December 16, 2004 Report Share Posted December 16, 2004 does the check engine light come on? Quote Link to comment Share on other sites More sharing options...
Jhobuu Posted December 16, 2004 Author Report Share Posted December 16, 2004 Actually, no. I haven't seen the check engine light on at all, other than when I first turn the key on. Quote Link to comment Share on other sites More sharing options...
Intlcutlass Posted December 16, 2004 Report Share Posted December 16, 2004 The plugs are fine... New actually, and I don't think that I EVER want to go through getting the back 3 in again. I know we are all very smart people, but mistakes can happen. When you did the back three , are you sure you got the firing order correct? Any codes? Is it misfiring? Quote Link to comment Share on other sites More sharing options...
Jhobuu Posted December 16, 2004 Author Report Share Posted December 16, 2004 The firing order is right, I checked twice before rocking the engine back into place. It doesn't seem to be misfiring, when there is no load on the engine, it runs great. I had the computer cleared when I took it in for the radiator, and I haven't seen the SES light since then. Quote Link to comment Share on other sites More sharing options...
no1kicker Posted December 16, 2004 Report Share Posted December 16, 2004 You probably have, but check the air filter and see if the cat may be clogged. If it has high miles it could be losing compression slowly. Quote Link to comment Share on other sites More sharing options...
Jhobuu Posted December 16, 2004 Author Report Share Posted December 16, 2004 Oh, don't say compression... A ring job is a bit beyond the scope of my toolbox right now... The air filter is clean. Old, but still white. And the cat is, well, non-existant. Once I saw that there are no air lines running out of the cat, I cut it out, and straight-piped it. No emissions requirement in my county, you see. I thought that might have been a cause, but the problem started long before I did that. Quote Link to comment Share on other sites More sharing options...
Regal_GS_1989 Posted December 17, 2004 Report Share Posted December 17, 2004 I'm going to say Dead Coil Pack. I'm 99% sure that is your problem. I have an 88 regal that has that problem. Except, only when it is really humid. It only cuts out when the coils are wet or damp. Anyways, the car is gutless, get horrible mileage, and also runs rough under load. So, I would start at the coils. Quote Link to comment Share on other sites More sharing options...
Jhobuu Posted December 17, 2004 Author Report Share Posted December 17, 2004 Any way that I can test for that without just replacing them all? Or are they cheap enough to do that? Quote Link to comment Share on other sites More sharing options...
Regal_GS_1989 Posted December 17, 2004 Report Share Posted December 17, 2004 Any way that I can test for that without just replacing them all? Or are they cheap enough to do that? Well, you probably want to replace all of them. But an easy was to test them is to unplug the plug wires from each coil pack. Then run the car. When you unplug the dead coil, the car won't seem to run any different. Just make sure not to unplug them when the car is running, or expect one hell of a shock. Quote Link to comment Share on other sites More sharing options...
SleeperRed90TGp Posted December 17, 2004 Report Share Posted December 17, 2004 Regal_GS_1989 I would say hit right on. any hesitation, staggering or stumble is going to be ignition. 99.999999 % I have been through at least 10 coils. Yes youcan checkt them out, get one known good coil (30new)and replace each one with the good one until you find the bad one. Piece of cake. Jud Quote Link to comment Share on other sites More sharing options...
Jcrow Posted December 17, 2004 Report Share Posted December 17, 2004 You can check the resistance of each one, compared to each other. Use an ohm meter. I'm not sure of the right value. Also you can crank it with a plug out and see what the spark looks like. white = weak blue = good Quote Link to comment Share on other sites More sharing options...
SleeperRed90TGp Posted December 17, 2004 Report Share Posted December 17, 2004 You can check the resistance of each one, compared to each other. Use an ohm meter. I'm not sure of the right value. Also you can crank it with a plug out and see what the spark looks like. white = weak blue = good That won't work. you can check resistance till your blue in the face and it will tell you nothing. Coils usually break down when they get hot or at different loads on the engine. Checking resistance will only tell you if you have a dead coil, no spark or never will spark. The absoulte best way to check our coils is replace one at a time with a known good one. Jud Quote Link to comment Share on other sites More sharing options...
buckethead Posted December 17, 2004 Report Share Posted December 17, 2004 I just replaced all 3 of the coil packs and the icm on my 2.8. Ended up being about $160 worth of parts (new parts, from advance auto)... I think it's a good idea to change your icm along with the coil packs as a fried coil pack can short out the icm. If you don't have one, get a hayne's manual and that'll tell you how to switch them out. My advice though, get a u-joint socket so you can reach the bottom bolt on the icm. I had a bitch of a time with that because my AC lines were right in the way. Also, get some of the dielectric grease to put on all the connections and the back of the icm where it mounts to the block. Quote Link to comment Share on other sites More sharing options...
SleeperRed90TGp Posted December 17, 2004 Report Share Posted December 17, 2004 I just replaced all 3 of the coil packs and the icm on my 2.8. Ended up being about $160 worth of parts (new parts, from advance auto)... I think it's a good idea to change your icm along with the coil packs as a fried coil pack can short out the icm. If you don't have one, get a hayne's manual and that'll tell you how to switch them out. My advice though, get a u-joint socket so you can reach the bottom bolt on the icm. I had a bitch of a time with that because my AC lines were right in the way. Also, get some of the dielectric grease to put on all the connections and the back of the icm where it mounts to the block. Not true. Believe it or not I am using my orginal ICM 200k and 14 years or is it 15?? Since I moved the coils up between the dog bones about 3 years ago I have not had a coil failure. Had 9 or 10 before moving them. The car seems to run ok to the tune of high 13's. Why spend 100 on and ICM if you don't need it. Lots of parts stores can test ICM's I would definatly do that first. They can also test coils resistance)but as I said the only real way to test them is to replace them. Jud Quote Link to comment Share on other sites More sharing options...
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