1999 dodge ram van 1500 5.9l engine.

So I posted a thread where my car wouldn't start without me giving it gas. I replaced the idle air control valve and that seemed to work. Unfortunately the problem is back, but slightly different now.
The car starts but seems to die on idle after it's warmed up. I replaced the IAC and things were good. The car almost overheated (fixed that problem by going back to stock fan) and now it seems this problem is occurring.
I just replaced the throttle position sensor and will be replacing the oxygen sensor. I was hoping the tps might help but it didn't. The 02 sensor change is just maintenance and hopes of fixing a rough idle.
Could almost overheating damage the iac? Could i be having fuel pressure problems?

Thx in advance

 

Clean out all the carbon in the throttle body. This should be done anytime you replace the iac.

 

Thx. Oddly enough, the problem has gone away the past two days. Any chance the ecu needed time to adjust to new iac and tps?

I rechecked the CEL light and it said there was an ecu problem and an iac problem. The store recommended checking the iac electrical, clean the tb, replace iac (which i already di along with tps) , or a vacuum leak.

I just dumped a can of tb cleaner in her although I didn't take the tb out.
Electrical connection looks ok although i didn't test with a meter (not exactly sure how).
I hear a hissing and think i may have a vacuum leak but when i sprayed starter fluid everywhere i didn't get a change in idle.

I resent that the chiltons manual doesn't specify where the vacuum lines are ot I would try a simple smoke test.

is it possible the ecu hasn't learned there is a new iac? It wasnt throwing ecu codes before and now the car is starting up and idling fairly well.

TIA.

 

Spray WD40 (NOT starting fluid, starting fluid defeats the purpose) near what you think might be the vacuum leak and if the idle drops.....

Check to see if the the brake diaphragm is faulty. Also replace, REPLACE the PCV valve. Forget about testing the PCV as I know from experience. That "shake test" isn't worth a d*mn.

I use upper case for emphasis and I am not shouting at anyone.

 

Seems like I had that problem in a Dakota 5.9 L where I had to keep my foot on the gas to keep it running when I came to a light.. If I remember right it was the battery believe it or not, at least in my case. It wasn't putting out full voltage so I think it messed with the computer. You might check the battery just to humor me.

 

Turns out it was the pcm. I ordered a replacement and the vehicle has been fine.