i cant get my car to idle anywhere close to what it should be at. im idling at about 1250. i have changed out the tps the iacv the thorttle body checked a million times for vaccum leaks tested the iacv and tps with a multimeter.adjusted the iacv adjusted the throttle stop screw and made sure that it was closing as far as i put the stop screw. just incase made sure the throttle coolent lines werent bent or crimped. what happens is i unplug the tps connectors to adjust the idle. i get it adjusted and its fine. i turn the car off plug the tps plugs back in and the idle goes right back where it was. i have tried adjusting it in diagnosis mode. i have tried adjusting it with the tps plugs in. i have tried it with the tps pluged in and in diagnositic mode. i cant figure it out. somone please step in and help. im sick of my car i dont even drive it unless i really really have to because the idle bugs me.

 

i also checked the intake and maf. and i really dont think its a leak anyways becasue i can get it to stay at the right idle speed for as long as the tps isnt pluged in.but then once the tps gets pluged in it goes back.

 

With the TPS unplugged you can adjust to the correct speed, but when you plug it back in it raises up to 1200 again? Something ain't right, sounds as if the ECU is over riding the idle for some reason. Is the reset screw on the side of the ECU in the center position? Sometimes if that screw isn't in the center of it's sweep, idle speed control problems arise.

 

I'm sorry if i'm de-railing the thread, but i'm idling kinda low. When i'm in P or N, i get about 700rpm. But when i go into R or D the rpm falls to 500rpm ( which according the site that i linked below, is low) wich causes my steering wheel to shake. The guy mentions about playing with the TB screw that adjusts the IDLE rpm. I think i know which screw he's talking about (it's the black plastic one right?), but i wanna make sure before i start turning things

http://home.earthlink.net/~maxfaq/maintenance.htm#idle

 

yes but you have to unplug the tps connectors first. and i will check my ecu. so the screw has to be all the way to the left but verticle? or all the way to the left?

 

nope tried it verticle all the way to the left and alined it with the blue mark on the ecu but not luck .

 

ok, i actually tried turning the screw without unplugging the TPS. I got my rpm up to 800 in P or N, but i'm still kinda low in R and D @ about 550rpm should i just keep turning the screw?

 

i;ve tried to adjust the rpm properly today (with the TPS unplugged) I'm almost to the point where i'm about to "unscrew" the idle adjustment screw, but things didn't change all that much.

 

have you tried adjusting the screw on the throttle body at all? bump for my question i still cant get it to idle correctly.

 

could my ecu be bad?

 

Have you checked the wiring to the ECM? What does the TPS voltage read on a scan tool? If you had a vacuum leak or bad MAF, you should trip a lean running code. Do you have any codes? Shoot me an email and I'll help you the best I can. mikem29ss@hotmail.com

 

Yeah, i was turning the black plastic-looking screw on the TB. It helped, my idle in P is good (about 800rpm) but the rpm in D & R are still pertty low ~550rpm. It seems like i'm about to take the screw out comletely,so i stopped turing it. Maybe i need some nice IACV cleaning.

 

there is no black plastic screw on the tb only on the iacv. the throttle body screw is small and metal and has a nut on it.

 

another thing is this all happened after i had taken my intake manifold off and put it back on. i got new gaskets and also got new bolts for the manifold. i torqued it to spec and in the right order. i have also checked many many times for a leak and made sure all the lines are pluged in. but why would it do it right after that. what really makes it hard to figure out is that with the tps unpluged it works. another question is there a way to check the tps harness. not the tps what are the readings supost to be?

 

Check that a wire didn't get pinched, also make sure all the hoses are where t hey belong. Also it doesn't take a big vacuum leak to affect it. Propane or a smoke machine is really the best method for checking leaks.

 

uh-oh, i guess i was turning the wrong thing then

So i'm supposed to be turning the small-metal-nut-screw

Thanks !

 

Have you cleaned TB with some spray & then idle went high, if so IMHO you will have to clean IACV.

 

i cleaned out the iacv and thorttle body at the same time.

 

how do you use propane to check for leaks?

 

bumpski.. ..

 

pluz one for teh bumpski

 

bump ditily umpski

 

That's a good question. My idle is too low and I'm pulling an 0603 code but I've replaced the coil pack, injector, new spark plugs all around, IAC valve cleaned, TB cleaned, k&n air filter cleaned and oiled.

I think I'm hearing a vaccume leak somewhere but I can't find it (I hear a strong sucking sound around the top manifold). I'd like to find out where to trouble shoot vaccume leaks too...

bumpy bump.

 

If I use a propane torch on low and wander around the engine hoses, if the engine starts to race where I have it, should this not be a good method? I remember hearing about it from my wife's uncle (automotive mechanic instructor at N.A.I.T.)

 

Wife's uncle and I fixed it. We followed the vaccume sound - my INTAKE manifold around cylinder 6 was pinched and was sucking in air. We took it off and replaced the rubber gasket.

I wonder how many of us are having issues with these crappy manifold gaskets?

 

well thats not my problem ive replaced all the gaskets twice. and torqued them to spec...

 

Have you checked your PCV valve to make sure it's not clogged?

 

ya i have checked it

 

I've gone through the same problem you have, since I just replaced my USIM with a MEVI. I had high idel problems and couldn't fix it. Have you checked the throttle cables? both throttle and cruise control. I made mine too snug and had to losen them.