dodgeman Posted March 20, 2010 Author Report Share Posted March 20, 2010 i guess i will just go back to gauges for now until i can try another ub3 Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted March 20, 2010 Report Share Posted March 20, 2010 that is correct. from what i gather there is no way that the digital cluster could cause these problems because the cluster does not control anything, it just reads the outputs exactly. Quote Link to comment Share on other sites More sharing options...
dodgeman Posted March 21, 2010 Author Report Share Posted March 21, 2010 ok, i got frustrated and put my anolog dash back in the car. it seems now that the car is doing the same thing with either dash installed or neither dash installed, so now it is just a basic why does my car run like this question. it idles, runs fine through the gears, but as soon as i get on it, now, no matter what gear i am in, then it starts to heisitate real bad until i let my foot off the gas, then everything is normal except the engine light comes on. one thing i have noticed is that it smells a little rich when i first start it up and let it run for a few min. any ideas this time. so, as long as i dont get on it, it runs fine, if i try to get on it that is when it starts to hesitate Quote Link to comment Share on other sites More sharing options...
AL Posted March 21, 2010 Report Share Posted March 21, 2010 I am thinking TPS... It may not be registering that you are at full throttle... Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted March 21, 2010 Report Share Posted March 21, 2010 O2/MAP/TPS how old are they and do you know how to check them? Quote Link to comment Share on other sites More sharing options...
dodgeman Posted March 21, 2010 Author Report Share Posted March 21, 2010 dont know how old they are, car has 60,000 miles on it and as far as i know never been changed. I filled up my car with gas the other day and it was almost empty when i did. (that is one thing i did before this happened.) drove through alot of standing water last week when we were getting flooded(that is the second thing i know for sure.) about 2 weeks ago after filling up with gas i put in about 3oz of lucas oil fuel treatment. could that stuff have caused my prob. Quote Link to comment Share on other sites More sharing options...
tornado_735 Posted March 21, 2010 Report Share Posted March 21, 2010 No the lucas wouldn't have caused it. I would guess the tps as well. If you can find someplace to get obd1.5 read this would end the guesswork. Quote Link to comment Share on other sites More sharing options...
dodgeman Posted March 25, 2010 Author Report Share Posted March 25, 2010 took the car to gm, they diagnosed it. 80 dollars later they say my crankshaft position sensor is bad and the pcm. i think i am going to do the crankshaft sensor first. what do you guys think Quote Link to comment Share on other sites More sharing options...
dodgeman Posted March 26, 2010 Author Report Share Posted March 26, 2010 sorry, misquote. not my crankshaft sensor, it is my camshaft positioning sensor, and the pcm, should i replace both now or do one at a time, and do you guys think the dealer diagnosis was correct. Quote Link to comment Share on other sites More sharing options...
tornado_735 Posted March 26, 2010 Report Share Posted March 26, 2010 sorry, misquote. not my crankshaft sensor, it is my camshaft positioning sensor, and the pcm, should i replace both now or do one at a time, and do you guys think the dealer diagnosis was correct. I would say so, although I was not aware a cam position sensor could cause intermittent stalling. I thought it was kind of an on or off deal. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted March 26, 2010 Report Share Posted March 26, 2010 if the cam sensor quits, then the PCM attempts to stay SFI by guessing(based on the last known pulse from it) which isn't too great of a method. i could see a stall during certain pulsewidths happening... i'd go cam sensor first. cheaper/more likely to be your issue. Quote Link to comment Share on other sites More sharing options...
dodgeman Posted March 26, 2010 Author Report Share Posted March 26, 2010 thanks i will do the cam sensor first then Quote Link to comment Share on other sites More sharing options...
dodgeman Posted April 6, 2010 Author Report Share Posted April 6, 2010 (edited) I replaced the cam positioning sensor and still does the same thing. I guess next will be the pcm. If i buy one from carquest do i have to have it flashed at the dealer. 1994 3.4L also had the fuel pressure checked it was at 40psi. mechanic said it was good. checked coils, they are strong and no bad plugs. But still hesitates and jumps at WOT Edited April 6, 2010 by dodgeman Quote Link to comment Share on other sites More sharing options...
tornado_735 Posted April 6, 2010 Report Share Posted April 6, 2010 Change that PCM, and if that's not the problem, then go back to whomever scanned it the first time, provide documentation that you replaced the parts the he said were bad, and demand a free re-scan. Quote Link to comment Share on other sites More sharing options...
dodgeman Posted April 6, 2010 Author Report Share Posted April 6, 2010 I will do that, it was done at the gm dealer here in town. do you know if i have to have a new pcm flashed at the dealer Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted April 6, 2010 Report Share Posted April 6, 2010 the 94-95 3.4 still use a removaeble MEMCAL, so no, you don't need it reflashed, you'll just have to transfer that over into the new one. Quote Link to comment Share on other sites More sharing options...
dodgeman Posted April 6, 2010 Author Report Share Posted April 6, 2010 so by transfering the MEMCAL i wont be transfering the problems with it Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted April 6, 2010 Report Share Posted April 6, 2010 so by transfering the MEMCAL i wont be transfering the problems with it if you still have problems with it, it's possible it is the MEMCAL that's causing all of this... Quote Link to comment Share on other sites More sharing options...
dodgeman Posted April 6, 2010 Author Report Share Posted April 6, 2010 car quest has the pcm for 65 dollars but they say it has to be flashed, so if i buy this new one from car quest i can transfer the memcal from mine and put it into this one. If it still acts the same way would you suggest me putting the new one back together as purchased and then having it flashed at the dealer? Or if i buy one at a junk yard would it just be plug and play also. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted April 6, 2010 Report Share Posted April 6, 2010 the 94-95 LQ1 doesn't use a FLASH PCM... Quote Link to comment Share on other sites More sharing options...
dodgeman Posted April 13, 2010 Author Report Share Posted April 13, 2010 I have noticed that the car runs perfectly when it is cold. the warmer it gets the worse the hesitation gets, it even backfires sometimes, but from a cold start in the morning i can stomp it and it runs like a raped ape. anything heat related that would cause this? Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted April 13, 2010 Report Share Posted April 13, 2010 heat makes fuel vaporize... Quote Link to comment Share on other sites More sharing options...
dodgeman Posted May 1, 2010 Author Report Share Posted May 1, 2010 ok, i replaced the camshaft postion sensor. i just replaced the ecm. those are the two things the dealer said were codes. it still stalls at wot. I had it scanned again after the computer replacement and it pulled the same camshaft sensor bad code. he cleared it with the scanner and it did it again. he said the new sensor could be bad. i guess it could be. he thought it was the coils doing it after the car warmed up. 2 very weird things happening. when the car is completely cold it will not hesitate and backfire, only after it warms up, and another thing is it will only do it when the Tach hits 4000. no matter what gear i am in, when it hits 4000 it starts acting up. someone mentioned before about some kind of speed sensor or something that tells the computer that the car is going a certain speed and at a certain rpms. any more thoughts on this before i shoot myself. thanks Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted May 1, 2010 Report Share Posted May 1, 2010 4K almost sounds like the rev limiter that gets applied in park... if you have someone with scanning capability, watch the PNP status while you're moving the shifter... if it never leaves park/neutral, that could be your issue... what happens if you SLOWLY get the RPMs up to 4K, like manually selecting 1st gear and not letting it upshift, just applying light even pressure until it hits 4K? and if a new ECM and cam sensor were put in, and it still throws codes, the wiring for it could be the issue there. Quote Link to comment Share on other sites More sharing options...
dodgeman Posted May 1, 2010 Author Report Share Posted May 1, 2010 going slow up to 4k is fine until it hits 4k then it starts. i will have the guy check it again with his scanner to see if moves from park. did any of the other stuff that was suggested in my last post make any sense, like the coils getting hot and sending wrong signal or the speed sensor thing . thanks Quote Link to comment Share on other sites More sharing options...
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