P1506 - Idle Air Control Overspeed - 03 Cobra

[groovyone]

Anyone else had this code pop up on their 03-04 Cobra? It just started showing up on mine. The car still seems to run great, and the code obviously only trips when slowing to an idle in traffic. I have not yet tried troubleshooting it, but I figured I'd ask here first.

Some specs on the car, it is a 2003 Cobra with the UPR Cold Air Kit, Stock MAF and upper tube, and an Accufab TB. It is also chipped. The car has been unchanged for almost 2 years now, so I am not sure what would cause it now. I admittedly have been remiss in checking the filter recently, so I need to do that anyway, but could a clogged filter cause this code?

Thanks for the help.

 

[Kilgore Trout]

IACs are a problem, try cleaning it.

 

[groovyone]

IACs are a problem, try cleaning it.

Yeah, that wouldn't surprise me at all. I am already on IAC #2, but it was replaced 3 years ago.

 

[groovyone]

Well, after searching the net some more, I think I may have figured it out. About 3 months ago I tweaked the TB stop so it would idle about 100-200RPM higher. Since then the temp dropped about 40 degrees too. I think if I just adjust the stop screw back in a little, I should get the sensor to quit tripping.

 

[Kilgore Trout]

That is not how you adjust your idle on these cars, best to never mess with that screw... You should def return it to where it was and reset your PCM.

 

[Uncle Meat]

Personally I never would have installed an aftermarket TB until your car actually needed one. The stock TB is capable of well over 500RWHP. The stock MAF is the main restriction in our intake path. More people have more problems with idle quality and cruise control operation after installing an aftermarket TB on these cars....

Just my 2 cents is all....

U.M.

 

[groovyone]

Personally I never would have installed an aftermarket TB until your car actually needed one. The stock TB is capable of well over 500RWHP. The stock MAF is the main restriction in our intake path. More people have more problems with idle quality and cruise control operation after installing an aftermarket TB on these cars....

Just my 2 cents is all....

U.M.

I am at 475 RWHP now and had installed it in anticipation of future work, but then my attention and funding has gone to my bike and my 98 Cherokee (mostly maintenance on the Jeep). I hadn't had any issues until now, and like I said, it just started when I foolishly messed with it.

Most of my work on the car has been a learn as I go thing, since I hadn't done much work on my 01 GT, and hadn't done much of anything to any of my previous cars. TB was once of the less effective places I spent my money, but I didn't know for sure until I tried it. I did actually dyno at 20 RWHP higher after that and new plugs, but weather may have played a part in that.