Camaro98

I started by changing my 4 year old battery out and testing my alternator, all that is fine. So I cancelled out electrical charging system. Here is what happens...when I'm driving for about 5-10 minutes and come to a stop at a light or sit in idle the car will stall. Usually if my A/C is on, it stalls faster than without, but regardless, it still stalls in idle either way. After it stalls, I have a hard time getting it started, it takes a few cranks or sometimes I have to wait a few minutes before trying again and then it will start up and run fine again, until eventually it stalls out of no where in idle. BUT, WHEN DRIVING THE CAR, THE CAR RUNS PERFECT, so I know its not plugs, wires, coils, etc. Someone said it "might" be either a fouled fuel filter, bad fuel pump, the crankshaft position sensor or more possibly the IDLE AIR CONTROL VALVE. Does anyone know what this might be? Have it happen to you? Do you think its the Idle Air Control Valve? How would I know if its a bad fuel pump? Like I said, the car runs PERFECT when it drives, but only stalls in idle occasionally. HELP!!!!

HAZ-Matt

iTrader: (8)

What car is this btw? Stock electronics and tune? Mods? Do you happen to have any scanner like HPTuners? No SES light right?

I would think if the CPS were the culprit you would see some erratic tach behavior. And it would probably have problems driving down the road.

I assume the voltage gauge looks good while at idle. You said you tested the alternator too.

I would think if you have absolutely no problems except at idle it should be something like the IAC that really only affects the idle. Make sure the hoses going to the throttle body are intact.

I don't think you could get a fuel system problem only at idle, but I am not an expert.

Camaro98

Thanks, ya I'm narrowing it down to that as well. This is on the 3.8L 1998 Camaro. With simple stuff like exhaust, intake, nothing special, daily driver. Ya it is just a wierd happening, because car drives perfect, and only stalls occassionally when in idle, not every time. I let my car sit in the driveway on for about 20 min in idle and didnt stall. But when I drove it about 8 miles up the road and came to a stop light, it stalled after a minute or so of sitting and waiting. Weird wierd wierd....I'm going to change out the IACV anyway and see what happens, or at least see if it has buildup of carbon on it, I know that can effect it.

Streetsharkls1

Unmetered Air, I Have The Same Problem

Streetsharkls1

Check For 0.6 Volts @idle On The Iac Also Check The Pintle That Comes Out Of Iac Then Retracts Its Sould Be 28mm/1.10 Inches Mine Was Longer, Have Someone Check If It Going In And Out.

needadvice

Under acceleration and even partial throttle a clogged fuel filter will still flow fine, but at idle the fuel might get slowed down enough to stall you. Change it, it'll take 5 minutes, then you can rule it out.

I've had a bad CPS and got NO codes at all. It acted perfect at times, and stalled like crazy and was hard to start at times. Sometimes it would start and run perfect for a whole ride from A to B, then give me all kinds of hassles when I tried to go to C. In my case, the only way to see if the CPS was bad was an OBDII scan.

edited: I put fuel pump instead of filter, oops.

Camaro98

What is unmetered air? Explain this....and how to check/fix bla bla? more info please....

proelky

iTrader: (13)

My car did that when the IAT sensor was going out. Randomly at a light, or idle...pulling into a parking lot it would try to die.