shipman Posted December 3, 2003 Report Share Posted December 3, 2003 I recently started having a problem where my 91 Lumina 3.1 idles very low (almost stalls) when I am in gear and stopped. I think it started after I replaced my fuel filter... I removed the fuel pump relay and turned the car over to run the gas out of the lines. Was this a no no? I read the thread from MidgetOnWheels, but I don't think it is the trans locking the clutch in when it is warm because it doesn't usually stall. It justs idles low and kinda rough. When I step on the gas it seems to hesitate a little before the throttle really kicks in. I am new to the boards... glad I found this site. Any ideas? Thanks in advance for any help! Quote Link to comment Share on other sites More sharing options...
gmrulz4u Posted December 3, 2003 Report Share Posted December 3, 2003 Besides just saying it's idling "low", can you actually specifiy how many RPM's it's idling at?? You should first understand that your ECM(Engine Computer) is constantly monitoring your engines RPM, and, when it finds that the actual RPM is 200 above or below what it has set as the "DESIRED IDLE" it will set a Trouble Code(35). If you had a Scanner, you could constantly monitor what your ECM WANTS the engine to idle at. With my car, it usually wants around 1000 RPMs when the engine is COLD, and around 650 when the engine is HOT. The fact that you don't mention whether you're getting a SERVICE ENGINE SOON light makes me wonder just HOW bad the low idle is. If your ECM wants it to be 700, and it's only 450, then you should definately be getting a SES light. Other than that, idle is primarily controlled by the IAC Valve... Quote Link to comment Share on other sites More sharing options...
hazmatic Posted December 4, 2003 Report Share Posted December 4, 2003 y not just try a idle relearn????? Quote Link to comment Share on other sites More sharing options...
PaPaPooh Posted December 4, 2003 Report Share Posted December 4, 2003 y not just try a idle relearn????? i would do that first and see if it fixes it 10 or 15 min of your times is better than running a scan Quote Link to comment Share on other sites More sharing options...
Slade901 Posted December 4, 2003 Report Share Posted December 4, 2003 Another thing that would be helpful with car idle is to remove the air intake box, line and replace your air filter if it is dirty. Clean the throttle body intake and remove the IAC and clean it as well with a throttle body cleaner and put everything back. Do an Idle re-learn after that. Quote Link to comment Share on other sites More sharing options...
quaddriver Posted December 4, 2003 Report Share Posted December 4, 2003 I recently started having a problem where my 91 Lumina 3.1 idles very low (almost stalls) when I am in gear and stopped. I think it started after I replaced my fuel filter... I removed the fuel pump relay and turned the car over to run the gas out of the lines. Was this a no no? I read the thread from MidgetOnWheels, but I don't think it is the trans locking the clutch in when it is warm because it doesn't usually stall. It justs idles low and kinda rough. When I step on the gas it seems to hesitate a little before the throttle really kicks in. I am new to the boards... glad I found this site. Any ideas? Thanks in advance for any help! everyone write this down, the easiest procedure for T code idle relearn..... yank the battery cable (ecm fuse does not hit NVM), go have some coffee, turn the key on while the cable is yanked (forced drain) key off, reinstall cable set parking brake, ac off, car in park, start car, place in drive, take foot off brake (hope that parking brake works) let the car idle until the cooling fan comes on NEVER hitting the brake and fer darn sure the AC is off (no defrost either) Once the cooling fan comes on, shut off car, wait 2, restart, drive around the block. done Quote Link to comment Share on other sites More sharing options...
shipman Posted December 4, 2003 Author Report Share Posted December 4, 2003 Thanks for the info guys. quaddriver - thanks for the info on how to relearn the idle. I was going to ask how to do that but you beat me to it! I'll give that a try and see if it works. I especially like the part about having a cup of coffee... I say the idle is "low" but it is more like an incosistent idel, like something is bogging the engine down. It happens when I am in drive and come to a stop with the brake on. The rpms go way down (about 500 or lower for a moment) and then it oscillates between 500 and 1000. On it's low swing you can see the headlights dimming. If I put it in park or nuetral the idle comes up to a nice consistent hum just under 1000. I just put in a new air filter, so that should be fine. I get a ses light periodically but it is not related. It occasionall comes on but then goes off on its own. I jumped the connector to get the codes and I've been able to see a 32 or something (can't remember exactly): EGR valve malfunction. But I am not getting an idle alarm. Slade901 - I'll also try cleaning out the throttle body and IAC (not sure where that is... I'll have to look that one up) and see if that helps any. I am more and more wondering if it has anything to do with the trans. For a while it had trouble engaging the clutch after coming to a stop in overdrive - like it was stuck in nuetral until I gave it enough gas. I figured some gunk in the trans clogged up a valve or something. It eventually went away but maybe this is related?? Thanks. Quote Link to comment Share on other sites More sharing options...
Slade901 Posted December 4, 2003 Report Share Posted December 4, 2003 Check this link out. http://www.v6z24.com/mods/howto/images/throttlebody/diagram1.jpg Quote Link to comment Share on other sites More sharing options...
shipman Posted December 15, 2003 Author Report Share Posted December 15, 2003 Strange... I haven't had the chance to try anything yet (idle relearn, IAC, etc.) yet it has cleared up on its own. Runs like a champ now. :? Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.