Help with P0505 - Idle Air Control Malfunction

[420aPJ]

tried just about everything replaced ecu , iac what else could it be. ive been reading the forums heavilybut i really can't figure it out. it has a low loping idle and sputters at wot. what am i not trying. maybe i installed the iac wrong. any input help

 

[99BoostedRS]

Did you check for vacuum leaks and also check the IAC circuit?

Forgot to say it could also be your TPS

 

[420aPJ]

I completely looked over the TPS. But no leaks and i will check the IAC circuit tonight.

 

[bullettdsm]

Any chance you do anything with the TB recently? Maybe a ported one or a 60mm? Just for funsies, take a look to see if the butterfly is slightly off center. Though I don't believe that would affect the sputtering at wot, its something "weird' to check.

MB

 

[420aPJ]

I haven't done anything to the throttle body. Maybe one of the previous owners. Its such an annoying problem. Also i forgot to add that my car drinks a but load of gas. like 100 miles per tank

 

[Slo2gen]

Did all of this just pop up when you swapped in the afx or was it there before you went with the afx ecu?

 

[420aPJ]

It was there before the AFX and i thought a new ECU would rectify my problem. I was wrong.

 

[bullettdsm]

I'll ask the obvious, no cels?

MB

 

[420aPJ]

It threw the P0505 but the check engine light went off. I will goto autozone today and have them scan again for stored codes. I did replace all injectors and had the throttle body off, so i will check that again today also.

 

[bullettdsm]

It threw the P0505 but the check engine light went off. I will goto autozone today and have them scan again for stored codes.

Cool. And yes, I meant any other codes

I did replace all injectors and had the throttle body off, so i will check that again today also.

Hmm, I find this interesting. Replaced the injectors. Why? With what? New or used? Larger or smaller? Same size? blah blah.

A dribbling/leaking injector or an injectors that are too big will give you the same symptoms that you speak of.

MB

 

[420aPJ]

Same size as stock. And i changed them cause the problem was happening before and the car was loping at idle so i thought.... "timing or injectors, what the hay lets do both." did the injectors and the problem was still there so i was sure it had to be timing. The intake cam was off one tooth but it still didnt fix the problem. I remembered reading in the forums that some peoples IAC went bad so i changed that next. All im left with is TPS sensor. I have no idea what else it could be. Im back in school so i really dont have time to do a complete diagnostics unless we can bring it into class or something. I just pray that its the TPS cause i cant find a vacuum leak. Would a video help?