What causes high engine rpm when starting a jeep?
A dirty air passage from the IAC can give idle problems. Remove the IAC stepper motor and clean the plunjer and air passage very well. You will have to remove the resonator box for this, because the passage starts at the front of the throttle body.
What does erratic idle mean on a jeep?
Erratic idle like you have is the TPS. A faulty IAC would give a constant idle (high or low) and a fault code for the IAC. Erratic is normally the TPS. If you have a scanner which shows live data, you can see the TPS % going up and down a bit. Its normally around 12 % at idle. KYB Gas-a-Just shocks / Transgo reprogramming shiftkit.
What does high idle RPM on start up mean?
The hose is going to the vacuum reservoir, which is used for the cruise control. I wrote a bit too early. Today on start up, high idle RPM. I took off the IAC stepper motor and it was very dirty, looked like carbon build up. Cleaned it up, started engine and sprayed cleaner in the throttle body and replaced.
What should the TPS be at idle on a jeep?
A faulty IAC would give a constant idle (high or low) and a fault code for the IAC. Erratic is normally the TPS. If you have a scanner which shows live data, you can see the TPS % going up and down a bit. Its normally around 12 % at idle.
A dirty air passage from the IAC can give idle problems. Remove the IAC stepper motor and clean the plunjer and air passage very well. You will have to remove the resonator box for this, because the passage starts at the front of the throttle body.
What to do if engine RPM is high on cold start up?
Fast idle on cold start up and takes 5-10 minutes to go back to normal. Outside temps are 100F so engine is not really cold. First clean the IAC stepper motor plunjer and air canal and check again. If still high on idle, then its probably the TPS. KYB Gas-a-Just shocks / Transgo reprogramming shiftkit.
What’s the engine rpm on a 2004 Jeep?
Recently started to have this problem…
7 HO. Fast idle on cold start up and takes 5-10 minutes to go back to normal. Outside temps are 100F so engine is not really cold.
A faulty IAC would give a constant idle (high or low) and a fault code for the IAC. Erratic is normally the TPS. If you have a scanner which shows live data, you can see the TPS % going up and down a bit. Its normally around 12 % at idle.
What’s the engine rpm on a new Jeep?
On startup, the RPM will climb up to 2,000 and then idle back down to around 6oo. It doesn’t matter if the engine is hot or cold. Engine is the 4.7 in a ’99 Could this be a function of the throttle position sensor and if not, what could cause this? Thanks This could have to do with the TPS, but also with the idle air control (IAC) stepper motor.
What makes a jeep stall on a cold start?
In the morning go to start the jeep and get out of garage. Let it warm up for several minutes. Put it in reverse and it would stall. Only happens when temp is below 20F. Ideas? I’ve heard some say that they put the TC in Neutral but put the Transmission in Gear to see if that makes a difference.
Fast idle on cold start up and takes 5-10 minutes to go back to normal. Outside temps are 100F so engine is not really cold. First clean the IAC stepper motor plunjer and air canal and check again. If still high on idle, then its probably the TPS. KYB Gas-a-Just shocks / Transgo reprogramming shiftkit.
When do RPMs drop on a cold start?
Towards the end of the winter earlier in the year, I dropped it off at the dealership overnight so they could see it happen in the morning, and they said “it didn’t happen”… and I don’t have time to keep doing that. It’s getting cold again here in PA and it is starting to happen again, so I will have to revisit the issue.