Thought It Was a Good Day Until...
Thread Starter
Racer
Joined: Jun 2011
Posts: 283
Likes: 5
Thought It Was a Good Day Until...
Hey everyone. Well, had a day off so I decided to install my injectors from FIC. I also had a code for high idle so I decided to clean my IAC. I took off the IAC and saw that it was gunky so I took some throttle body cleaner and sprayed it until it was clean. I didn't take off the throttle body to clean so I sprayed throttle body cleaner in the throttle body and the hole for the IAC. Put the IAC back on and swapped out my old injectors. It wasn't too bad, took just about an hour. When I started my car, the idle jumped up to about 2500-2800 rpm and stayed there even after the car was heated up. Put it in gear and the idle stays at 1500 rpms. Idle never came back down. Went and unplugged the connector for the IAC just to see if it would do anything and the rpms flew up to 2500 rpms again. Did I mess something up with the IAC or do you think I need a new one? I also found these 3 things sitting where the injectors go. Could these parts have fallen out of something while I has cleaning the IAC? Here's a picture of the things I found. Would have been great if the car ran well after installing the injectors and cleaning the IAC.
Thread Starter
Racer
Joined: Jun 2011
Posts: 283
Likes: 5
I didn't put it on my post but it's a 1996 coupe auto. The first thing I did was jump onto the highway. Went up to about 65mph but high idle problems were still there after getting off. I don't know if it matters but while on the highway I switched from drive to overdrive and the rpms dropped like normal. I just pulled out the IAC but I don't know what I'm actually looking for. I sprayed the unit and spring with throttle body cleaner earlier to clean it but I'm not sure if it's just broken. Is the spring supposed to compress when you push down on it from the pintel? I tried to push it down but it's stuck and nothing compresses. Does that mean the IAC is faulty? I just ordered a new IAC but it'll take a couple of days. Thanks Tom.
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
I'd replace the IAC at this point too. I don't believe that you're supposed to push in on the pintle. If you have access to a scan tool, you can see what your IAC counts are (pintle position) -or at least what the ECM is calling for. If a scan was showing a low number but your MAF G/sec are high and idle is high, that would pretty conclusively show that the IAC is toast.
You're sure you don't have any big vacuum leaks?
You're sure you don't have any big vacuum leaks?
Thread Starter
Racer
Joined: Jun 2011
Posts: 283
Likes: 5
I'd replace the IAC at this point too. I don't believe that you're supposed to push in on the pintle. If you have access to a scan tool, you can see what your IAC counts are (pintle position) -or at least what the ECM is calling for. If a scan was showing a low number but your MAF G/sec are high and idle is high, that would pretty conclusively show that the IAC is toast.
You're sure you don't have any big vacuum leaks?
You're sure you don't have any big vacuum leaks?
Thread Starter
Racer
Joined: Jun 2011
Posts: 283
Likes: 5
Well, I took it up to 60 on my test drive but maybe I didn't drive it long enough. What about people saying to step on the gas, start it for 5 seconds, shut it off for 10 seconds and turn it back on. That's why I'm asking because some say it will reset after driving past 35 and others that it reset doing the on off routine. Hopefully it's a faulty IAC since I already have one ordered.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
I answered this in the other thread you posted on this subject, but for the sake of thoroughness...
You should retract the pintle on the IAC before you install it. I did it by pushing it against the edge of my workbench with my leg. I couldn't press hard enough with my fingers. If the pintle is extended too far when you install it, it can bottom out and break the plastic guide it rides in.
A scan tool can be useful in a situation like this. I have heard that the IAC counts will go to zero if you have a vacuum leak. That makes sense because the ECM/PCM is trying to shut off the extra air. This would only apply in closed loop mode when the ECM/PCM is monitoring the AFR with the O2 sensor(s).
You should retract the pintle on the IAC before you install it. I did it by pushing it against the edge of my workbench with my leg. I couldn't press hard enough with my fingers. If the pintle is extended too far when you install it, it can bottom out and break the plastic guide it rides in.
A scan tool can be useful in a situation like this. I have heard that the IAC counts will go to zero if you have a vacuum leak. That makes sense because the ECM/PCM is trying to shut off the extra air. This would only apply in closed loop mode when the ECM/PCM is monitoring the AFR with the O2 sensor(s).
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Team Owner
Joined: Aug 2004
Posts: 21,543
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From: Park City Utah
Thread Starter
Racer
Joined: Jun 2011
Posts: 283
Likes: 5
So what is the correct method of resetting the IAC? Is it drive it 35 mph and above? For how long? Or the gas pedal method? With the gas pedal method, 1st you step down a little on the gas, start it and wait 5 seconds but are you supposed to keep your foot down on the gas for the 5 seconds or step down on the gas pedal until it starts. Then turn it off. Then you're supposed to wait 10 seconds and restart. So which way is it supposed to be for my 96 coupe auto?
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
Thread Starter
Racer
Joined: Jun 2011
Posts: 283
Likes: 5
When I searched on this forum and on google, these 2 methods are what came up. Actually, the gas pedal method came up a lot more but it didn't say for what years.. I'm going to try both methods when my parts come in so hopefully it'll work.