Delay in acceleration and startup idle issue

[rodalt02]

I cleaned MAF after installing ECM, TPS, aclv and having dealer do a idle relearn and key reprogram. The car runs great with these two exceptions: 1) In the morning I have to keep accelerator pressed for a minute in order for the car to properly idle and 2) When I really step on the gas the car hesitates before picking up speed.

I know it may be the MAF or a bad ACLV, but I was told today that it could also be a faulty fuel pump. Has anyone ever had these issues and if so, what was the outcome? Thanks.

[MinisterofDOOM]

I would test your fuel pressure. Fuel pump is a possibility, especially with hesitation under throttle.

[rodalt02]

I had the fuel pressure checked and everything was normal. I then decided to see if any codes existed even though the SES light was not on. I found two codes, a P505 and a P430 code. I wonder why the codes did not throw a SES light. I guess I had better take out the ACLV and send it back before it fries my ECM again. Could this be the reason I have to put my feet on the gas to start my car and if it still starts and runs okay, do you think my ECM is okay.

Also, could a reflash at the dealership fix all of this since i installed a new MAF without doing the relearn?

[loystock]

We are here to help all club members. But this one is....

This has been an on-going saga that started way back in Dec' 09. Had you listened to us, your problem should have been resolved long time ago. It all started when you bought a used car with multiple problems - bad electronic engine mount which 'fried' the ECM as well as defective IACV (P0505) and TPS. You opted to have the ECM rebuilt and we provided you with suggestion about what to do after the rebuilt and IACV replacement

When you went to the dealer for reprogramming of rebuilt ECM, you were told that the replacement IACV is 'sticky' and that the MAF sensor is also bad. Based on the symptoms you provided, we concurred with the dealer findings. Yet you did multiple postings (9 ea?) trying to find ways to avoid replacing the IACV and MAF sensor. You eventually replaced the MAF sensor and is now planning to replace the IACV.

Now you have codes P0505 (IACV, back to original problem) and P0430 (new problem, Catalyst Efficiency Below Threshold, Bank 2). Unless you replace the defective replacement IACV, your ECM may be 'fried' again. Due to the delay in correcting the problems, your car may have been running rich for a while which probably caused your catalytic converter (Bank 2) to fail. Rich mixture for extended period of time may cause the 'cats' and O2 sensors to fail prematurely (fuel accumulation in the cat may even ignite).

I know money is tight nowadays but you will incur more expenses unless you correct the existing problems.