High Idle issues

[mongule]

I am running an OBD2 m52 and I just got a new maf. But after I installed it i started to have some weird idle issues.

Idle would go straight to 2000-2200 and stay there.
Now I beleive this is not a problem with the maf due the car doing the same thing with a different maf.

I've checked for vacuum leaks and have not found anything.
I'm suspecting the ICV so I removed it and cleaned it and this helped bring the car to stumbly idle (when jsut started) at more normal revs put if you tap the gas revs stay at 2000 again.

So I ordered a new ICV but I was wondering for any other suggestions

Thanks

[jrdeamicis]

The still sounds like a vacuum leak.

The revs holding after bouncing the throttle

[mongule]

Ok well a little update i got a new ICV, changed it and still the same problem.

If I disconnect the ICV idles searches but it in normal range 600 to 1k type of thing and also pressing on the throttle doesn't result in a high idle .

So this looks to be a wiring issue?

Any input would be helpfull.

EDIT:

Another question. What are the inputs the DME uses to control the ICV? EX: if my TPS is messed up would it affect the ICV . But i'm looking for all possible inputs.

[mongule]

Ok so unplugging the tps does absolutely nothing.

Is this normal?


TPS was tested with a multimeter and everything is in spec with the bentley...

At this point any input would help.

Would a faulty coolant temp switch ( the one to the dme) cause this?

[10Toes]

Is your throttle cable allowing your throttle body to close all the way?

[mongule]

yep throttle plate is fully closed

[matt]

Have you read out your DTCs? If you can give a list of codes present, that will help a lot.

Would a faulty coolant temp switch ( the one to the dme) cause this?

Even if the ECU thinks it is at it's minimum temp, the max fast idle speed in the stock software is ~1280 if I remember correctly.

[sushipower]

Check to see if air temp sensor and coolant temp sensor are reversed.

[mongule]

Hey matt I don't have a check engine light or a peak tool.

I will try to make the check engine light work and look for codes.

The sensors are connected fine also.

What I find odd is the fact that once the car is warm, it eventually finds an idle. This to me points to vacuum leak but I can confirm its definitely the ICV that's staying open and that there are no vac leaks.

I've driven it as it is twice now to work (5 minute ride) and it stumbles and hesitates also.

The Bentley only has specs for the tps for the OBD1. Are they the same for OBD2 to test it. Because if so, then my tps might be bad.

[matt]

Check engine light won't tell you anything on an OBD2 car, there is no such thing as a stomp test. You need a Peake tool or even a generic OBD2 scantool. Depending on what you have wired where you may need an adapter to make the OBD2 tool work.

[mongule]

ok. I do have a generic scan tool. But I only have the engine diagnostic port.

guess I need some kind of adapter


But do you know about my other question regarding the bentley tests?

[matt]

www.obd2cables.com has an adapter.

Dunno on the other question.

[mongule]

alright thanks for the link

I believe it must be the same otherwise Bentley would have different values i imagine.

Guess I'll be driving the aspire for a week or so

[mongule]

Ok I got my adapter cable from them. Its nice.

I plugged it in and instantly pulled 9 codes with my cheapo OBD2 scanner

Now in my troubleshooting of my issue I pretty much unplugged evrything at least once so i had a few codes.

Anyways after clearing them,

I get

P0121 ( TPS Range fault) this was one of the main things i was suspecting)

P0451 ( which is related to emmisions)

Now I guess I will get a new TPS and see if ti fixes my issue.

So just wanted to up date this.

The adapter they sell works perfect.

On a side note I was happy my DIAG port was wired correctly.

[matt]

So your car is now driving fine and those are the only two codes you get?

P0451 is your gas tank pressure sensor. At some point I will be able to flash that out.

You want to fix the TPS thing for sure.