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Today, when I started my car, it started, then immeduiatly dropped to 500 RPMs, and was struggling to keep running. It was fine after I shifted it into drive. I was in there with it idling before for 30 minutes, and it was fine. I then went to eat, and ten minutes later, it does that. Itss done it a couple times before. Whats the problem?
 

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Could be a dirty/faulty Mass Air Flow sensor, or a dirty/faulty Idle Air Control valve...

Start off by cleaning the MAF sensor (check the Technical Articles under Intake), and see if that helps any. I usually reset the PCM after cleaning the sensor, then I drive the car at 50-65mph for about 10 miles.

Try a search here on rough idle, and see what's been posted.
 

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My car just started the same ****, the IAC looks new, the prev owner said it did this, and I had no prob for the first 2 or 3 months I owned it, until yesterday.

I am going to see what the tech article says about cleaning the maf.

I did drive the car home w/o an air filter, man, the 3.8 NA ia friggin' slow, I came off of an SC to this, arg! lol...
 

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How old and type of Plugs?
 

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it wouldnt be the MAF because for the first 30 seconds of startup the car is in open loop running on a preset program from the eec. The IAC should be the culpirit since that starts working right after startup to let the car idle.
-Thomas
 

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Thomas said:
it wouldnt be the MAF because for the first 30 seconds of startup the car is in open loop running on a preset program from the eec. The IAC should be the culpirit since that starts working right after startup to let the car idle.
-Thomas

The idle kicks up high and then it tries to stall itself.

So clean the IAC then? How do I go about that?
 

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It could also be an air leak somewhere in your intake tube between your MAFS and TB. I tried to rig one up one time and had a leak which caused it to idle rough and low and eventually cut off. Once I found the leak and tightened it up, it solved the problem. Of course, this would only really apply if you have rigged something else in place of the OEM one. This is just a possiblity, but like Thomas and IronChopz said, it's probably the IACV.
 

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I have the stock tube right here on my kitchen counter, and I did check for cracks and such, the tube is still flexible.

I just need to know how to clean the IAC.
 

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I have no idea how to clean it, I just ordered a new one from Dan yesterday. It was about $60 with gasket
 

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the 3.8 IAC is a bit cheaper. I've actually got one right here if you want it. I upgraded to the 5.0 60mm tb and have that IAC. But try cleaning it first. It's located on top of the throttle body, unbolt the two bolts, spray some carb cleaner in the iac and clean it out with a rag as best you can, and clean the mounting plate on the throttle body too, bolt it on and see if that helps.
-Thomas
 

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I will try that and see how it goes.

The 5.0 TB bolts up to the 3.8 intake?
 

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sc0tty8 said:
The 5.0 TB bolts up to the 3.8 intake?
No, I have an adaptor plate but you could drill new holes into the throttle body. I also spliced in the 5.0 wiring harness for the tps and iac, and the throttle linkage bracket is modified too.
 
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