Lumina idle..video inside! **Update Top of Pg.4**

[1990lumina]

Hey guys this has been an issue with my Lumina for probably a year now..I never used to care but it seriously bothers the hell out of me now.

 

I think the video describes it best:

http://media.putfile.com/DSCN3741

 

The idle jumps up and down - especially in park and neutral..sometimes it'll stall itself out, or if I give it gas while doing that it bogs hard at times. Not sure what is causing that but it's annoying, any tips?

 

Thanks

[White93z34]

what if anything has been replaced recently?

 

Have you changed the IAC? if not I would start from there, followed by checking/replacing the TPS.

[1990lumina]

IAC was cleaned last fall, but no it has never been replaced. TPS = throttle position sensor?? I will check that tomororw after work.

 

Sorry, I should have mentioned..last fall car got a full tune up (fuel filter, plugs, throttle body cleaned, egr cleaned, tons of injector cleaner has gone through it, O2 sensor is new.

 

What does the TPS have to do with the idle? I honestly dunno wondering it's impact on idle?

[Q-Ball]

My car did the samething. It happend after it warmed up and I was at stop lights. FUEL FILTER!

[nebojsa_o]

Mine did the same thing when my EGR needed cleaning... And my buddies did the same thing when the hose for the PCV valve was cracked... I don't know if that makes any sense, but that was the only thing we replaced, and it was fine right after that. If you need any parts that are easy to take off of a 3100 Cutlass, you can borrow some off the Cutty. Seriously.

[5speedz34]

I would run Seafoam it for good measure, since its been a year.

 

The TPS tells the ECM how far opened/closed the Throttle plate is.

 

I would also check your upper intake plenum gaskets.

[1990lumina]

Does the TPS have anything to do with what gear the transmission selects to go into after a long coast followed by some gas. I'm sure throttle position + wheel speed would gauge what gear the tranny goes in? If so, my TPS may be screwed up.

 

Anyways, where is the TPS located and how do I check it? My Haynes book has nothing in it about the TPS from what I can see.

 

The pintle popped off the IAC today, I put it all back together and it moves in a out very freely so I'm assuming it is working half decent. Then again the motor idled the same (shitty) with the IAC taken out of the engine bay..so yeah..

 

Do I check those gaskets by spraying carb cleaner?? I was also looking for broken vacuum lines but am fiding it hard to find most of them (I assume they are all under the plenum?) It's a rhythimc rev up and down..I remember out lawn mower used to do that - the governor would open and close every second..we fixed it by jammed a screw into the carb to keep the governor wide open lol

[ns87]

to me, it sounds like the car is not getting enough fuel. fuel filter, but honestly it sounds like when I had a bad injector or 2.

[Andrew]

im thinking IAC or some kind of vac leak.

[1990lumina]

It's raining today and was horrible. I guess I could change the fuel filter again but it was done last fall during the tune up..unless I got some bad gas and clogged it up.

 

Any way to check injectors? I wouldn't doubt if I had a bad one.

[slick]

It was raining and it was noticeable worse? Are you sure water isn't splashing up on your ICM/Coils? Water could also be splashing at any form of gasket, CPS, etc...

[nebojsa_o]

I think he meant the day was horrible. It truly sucked here today. Zero motivation for anything... Good luck Jeff, but tit's ok, you'll finger it out!

[1990lumina]

It was raining and it was noticeable worse? Are you sure water isn't splashing up on your ICM/Coils? Water could also be splashing at any form of gasket, CPS, etc...

 

Yes, exactly. It was raining and noticeabley worse. Like the idle bounced up and down between 250rpm-1000rpm and at times would make the car want to move forward at a stop light with the constant erratic idle.

 

It's possible my coils/ICM are either getting wet or one is on it's way out. Think it'd help if I pulled plugs and see if any are wet, etc??

 

I think he meant the day was horrible. It truly sucked here today. Zero motivation for anything... Good luck Jeff, but tit's ok, you'll finger it out!

 

Yeah that too..plus work went nice and long today which wasn't supposed to happen

[chadz34]

Sounds like a fast vaccuum leak, I def wouldnt rule out fuel filter.

[89SupremeCutty]

It was raining and it was noticeable worse? Are you sure water isn't splashing up on your ICM/Coils? Water could also be splashing at any form of gasket, CPS, etc...

 

Yes, exactly. It was raining and noticeabley worse. Like the idle bounced up and down between 250rpm-1000rpm and at times would make the car want to move forward at a stop light with the constant erratic idle.

 

It's possible my coils/ICM are either getting wet or one is on it's way out. Think it'd help if I pulled plugs and see if any are wet, etc??

 

I think he meant the day was horrible. It truly sucked here today. Zero motivation for anything... Good luck Jeff, but tit's ok, you'll finger it out!

 

Yeah that too..plus work went nice and long today which wasn't supposed to happen

 

i'd get a spray bottle on a nice day out and start spraying water near the coils and ecm while it's running. pulling the plugs to see if they're wet wouldn't help.

[1990lumina]

It was raining and it was noticeable worse? Are you sure water isn't splashing up on your ICM/Coils? Water could also be splashing at any form of gasket, CPS, etc...

 

Yes, exactly. It was raining and noticeabley worse. Like the idle bounced up and down between 250rpm-1000rpm and at times would make the car want to move forward at a stop light with the constant erratic idle.

 

It's possible my coils/ICM are either getting wet or one is on it's way out. Think it'd help if I pulled plugs and see if any are wet, etc??

 

I think he meant the day was horrible. It truly sucked here today. Zero motivation for anything... Good luck Jeff, but tit's ok, you'll finger it out!

 

Yeah that too..plus work went nice and long today which wasn't supposed to happen

 

i'd get a spray bottle on a nice day out and start spraying water near the coils and ecm while it's running. pulling the plugs to see if they're wet wouldn't help.

 

I meant as far as a leaky injector or something..plugs wet with gas. Sorry I should have clarified.

 

Today though I got a nasty smell of rotten eggs in the car after idling for a long time in stop and go traffic...think my cat is packing it in? Or could it be there is raw fuel going through it and it's getting plugged up/overloaded by hyrdrocarbons?

[ns87]

See if the CAT is unusually hot, if not its deff a fuel issue. Listen to this video and see if its similar.Ignore the clanking (idk what that was!) This is when my fuel pump was dying, and yours sounds like a less extreme version of my video

 

[1990lumina]

See if the CAT is unusually hot, if not its deff a fuel issue. Listen to this video and see if its similar.Ignore the clanking (idk what that was!) This is when my fuel pump was dying, and yours sounds like a less extreme version of my video

 

 

Yeah mine sounds like that as well. I need to find some time to diagnose more though..this Friday I'm done class at 12 so I have all afternoon hopefully.

[1990lumina]

Okay UPDATE:

 

Car is getting HORRIBLE fuel mileage as of this tank. So I want to rule out a fuel delievery problem..it seems to be getting too much.

[5speedz34]

Just because its getting horrible fuel mileage doesn't mean its getting to much fuel.

[1990lumina]

I've been too busy with everything going on around here lately, and the car sort of cured itself, until tonight.

 

Sitting at a stop the engine will put constant load to transmission, so when I let my foot off the brake it'll lurch forward, and stopping sucks too because the motor won't stop pushing the car. If I pop it into neutral the motor will hold the revs at 2000rpm. If I tap the gas pedal they will go back to idle speed, but it's a very very rough idle, and after about 10 seconds of rough idle the revs go back to 2000rpm.

 

FINALLY the fucking SES light came on:

 

Code 35 -> Idle speed error...wow couldn't get anymore vague then that. Haynes manual recommends replacing the IAC but warns it may not fix the problem. Guess I'll go buy a new one of those and cross my fingers.

[mfewtrail]

Here ya' go Jeff...

 

http://www.w-body.com/ecm-codes.html#35

 

I'll post some pictures/scans from a factory service manual tomorrow that go into detail about troubleshooting this code.

[19Cutlass94]

Jeff, if you need a IAC or TPS or anything Ive got a million sensors at home Ill give to you, just pay shipping.

[1990lumina]

New IAC fixed the extremly high idle issue (2000rpm constant speed, etc..) but it still has a rhythmic "hunting" up and down so it's not fixed 100%

 

Jay, how much is shipping to Canada, postal code S7J5G5? I'll give you a couple bucks for the sensor too. I guess I'll try a TPS, got screwed $70 on the IAC @ Napa lol..oh well w/e.

 

I checked as much of the vacuum stuff as I could today. Everything seems to be fine vacuum wise..sprayed everything with carb cleaner quite extensively and nothing changed in the idle.

 

When I accelerate I still have power and everything...I don't think it's a fuel issue because it accelerates fine and passes on the highway fine still.

 

My Dad said it sounds like it isn't getting enough air, but that doesn't make sense says the acceleration and power is still there.

 

It seems like the engine is idling too low though, like 500-600rpm instead of the correct 800ish rpm..could it be that my ECM is going bad, or is it a sensor (TPS was hinted at)?

 

I'm at a loss with this, at least the car isn't trying to idle at 2000rpm anymore.

 

Thanks for the help guys!

[93CutlassSupreme]

I wouldn't install a new TPS until you'd done all other options. I've never seen/heard of a new TPS fixing ANYTHING.