sdwhite Posted March 8, 2004 Report Share Posted March 8, 2004 Hello all. I have a '93 3.1 and in the last year I've replaced the TPS, IAC, Ignition coil, Spark Plugs, Wires, fuel filter, anti-knock sensor, O2 sensor,coolant temp sensor, fuel pressure regulator, and my kitchen sink. When the pressure regulator was bad it was pumping extra gas into the throttle body. Now that it's replaced, I have a new issue that began the day before I repaired it. When the engine is warm and you come to a stop the engine wants to maintain a high idle. When the vehicle hits precicely 3 MPH, the idle drops and the engine starts bucking and coughing. After a few moments it will adjust enough and the idle will smooth out. If I let the car idle forward, when it hits 3 MPH the idle will jump back up again. It wont do it when it's cold and gets worse the hotter it gets. Do I have another problem or does the ECM just need to adjust something? Quote Link to comment Share on other sites More sharing options...
Guest TurboSedan Posted March 8, 2004 Report Share Posted March 8, 2004 have you disconnected your battery recently? it sounds like you need to do an idle re-learn procedure. otherwise it could possibly be your VSS - have you checked codes yet? joshua Quote Link to comment Share on other sites More sharing options...
Slade901 Posted March 8, 2004 Report Share Posted March 8, 2004 Yeah, I agree with doing the IDLE-relearn first. BTW, make sure that the TPS bolts are tightented up good and not loose. If you have tried cleaning or squirted throttle body cleaner on the TPS, that will ruin the TPS. You can't clean the TPS. When you replaced the IAC, make sure you have cleaned the hole where the IAC goes in because it is dirty. Quote Link to comment Share on other sites More sharing options...
sdwhite Posted March 8, 2004 Author Report Share Posted March 8, 2004 I got a bottle of TB cleaner and sprayed the pi$$ out of the passages on top, though not specifically the hole where the IAC goes from the IAC side. I was having this problem *before* I disconnected the battery a couple days ago, and *before* I changed the TPS. In fact it was due to this problem I thought I needed a new TPS. Since I was having the problem when I hadn't disconnected the battery for almost a year I don't think it needs to relearn the idle. Got me on this one. What's a VSS?? I can't seem to find my code reader or else I'd have them for you...looks like I'll have to bend a paperclip... What, precicely, is the idle relearn procedure (just in case I become desperate...)? Quote Link to comment Share on other sites More sharing options...
Slade901 Posted March 8, 2004 Report Share Posted March 8, 2004 VSS (Vehicle Speed Sensor) Quote Link to comment Share on other sites More sharing options...
musthavemuzk Posted March 10, 2004 Report Share Posted March 10, 2004 sounds similar but not quite what my new car is doing. new car is a 93 GP LE 3.1 sedan no need for a code reader to pull a code. saw this over at 60degree tech section http://www.60degreev6.com 1987-1993 ECM Code Retrieval Yes there is a way to retrieve codes yourself, but, it only works on models from 1987 - 1993! Find the "Assembly Line Communication Link (ALCL)" it usually found under the dash near the steering column. Now locate terminals "A" & "B", the 2 uppermost right-hand terminals, "A" is the one the right. You must use a short wire to ground out these terminals, or a hairclip, paperclip, or something similar. Short the terminals with the ignition off, then turn the ignition to "on" but do not start the car. The ECM will display "Code 12" by flashing the "Service Engine Soon" light indicating the system is working. Code 12 is simply one flash, followed by a brief pause, then two flashes in quick succession. This code will flash three times. If no codes are stored code 12 will continue to flash until the ground is removed from the terminal. After flashing three times, the ECM will display any stored trouble codes. Each code will be flashed three times then code 12 will be flashed again indicating display is completed. Note: If the trouble is intermittent the engine light will come for about ten seconds then go out. If the trouble is more serious then the engine light will stay on and the trouble codes stored in the ECM memory until voltage is interrupted to the ECM. To clear the codes, disconnect the battery for about ten minutes. Note: If you or anyone else has disassembled the lower footwell shield (with the diagnostic connector and courtesy light in it) it is possible the connector was reinstalled upside down. In this case, the uppermost right 2 terminals are no longer A nd B! No damage will be incurred if you short these two in this instance, but you will get no codes. If this happens, try the bottom 2 terminals on the left side! codes i pulled tonight when i looked were 23 and 43. so hopefully i can find something out tonight in my searching so i can get parts tomorrow and get her fixed. Monty Quote Link to comment Share on other sites More sharing options...
sdwhite Posted March 10, 2004 Author Report Share Posted March 10, 2004 I'll do the paperclip thing and see what I get. I disconnected the battery when I replaced the TBS to rid it of any old codes and start off fresh. Twice it idled rough enough for something to trip the MIL, though it went off when the idle stabalized. Are we sure that a 10lb. "fine adjustment" hammer might not clear this problem up? Quote Link to comment Share on other sites More sharing options...
sdwhite Posted March 10, 2004 Author Report Share Posted March 10, 2004 I did the paperclip thing and in the process of looking for a pen to write the codes down I found my code reader. Go figure. I gots me two codes. 33, a MAP sensor malfunction. 35, an Idle speed error. Do they sell these neat little Tech 1 scan tool things somewhere? The whole kit and kaboodle is run by the damn computer and you can't get anything out of the engine service manual unless you've got it hooked up. I think I'm gonna just junk the damn thing, move into a cave and fling dung at people. Quote Link to comment Share on other sites More sharing options...
musthavemuzk Posted March 10, 2004 Report Share Posted March 10, 2004 now how much fun can slinging dung be? not much if ya ask me. in my thread there are some suggestions to make sure things are plugged in and such before i go spending any money. so that is what i am going to do. then go from there. Monty Quote Link to comment Share on other sites More sharing options...
musthavemuzk Posted March 12, 2004 Report Share Posted March 12, 2004 went to post another reply yesterday and lost the forum so here it is http://www.w-body.com/ecm-codes.html i thought there was a page like this over at http://www.60degreev6.com but i cannot find it right now the haynes manual says 33 is a bad MAP sensor. to replace it 35 is a idle speed error. says to replace IAC i see you replaced the IAC recently mayb all that extra gas being pumped in fouled the IAC. Monty Quote Link to comment Share on other sites More sharing options...
god910 Posted March 12, 2004 Report Share Posted March 12, 2004 Sounds alot like how my car was acting when I DESTROYED my vacuum lines. Might not be a bad idea to check those out. Yeah, don't run and spend the money on a new map just yet. If you unhook the vac. line running to it, you will get a code 33. Doesn't mean you need to replace it, just means it's not matching the cell that the ECM thinks it's supposed to be in (based on TPS signal) no vac.=WOT, TPS at 3%=not WOT, you do the math. Quote Link to comment Share on other sites More sharing options...
musthavemuzk Posted March 13, 2004 Report Share Posted March 13, 2004 finally got to look at my car tonight. before i bought anything i got to feel behind the engine for the knock and crank position sensor. the CPS seemed to be fine by feel. the knock sensor on the other hand was wierd. finally determined that it was broken. so we removed it and i ran to get a new one before they closed. much better now. idle is still a touch rough but not terrible like it was. i do think the TPS needs to be replaced now. or something else. have not narrowed it down yet. slight throttle is fine but the more you go the less response you get from it. up until WOT then you get a little better. this leads me to think TPS good luck Monty Quote Link to comment Share on other sites More sharing options...
sdwhite Posted March 14, 2004 Author Report Share Posted March 14, 2004 I'm still curious why it surges above 3mph and chugs below. I suppose I could clean the IAC again but I think it's something else... Quote Link to comment Share on other sites More sharing options...
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