gamboni

I can't figure this one out...please help..On first start up while cold, the jeep runs great. After a couple minutes, the engine RPM's start to rev while idling AND while driving. RPMS go from 500 to 2,000 then the engine shuts off if I am stopped. .This whole scenario is intermittent,

The jeep first started doing this last winter but ran great all summer while it was warn and just started again as it got colder this fall. The jeep has been in the shop twice and they cannot find any problems. These codes showed up last week, but I think it seems like an issue with temperature not the TBS or MAP sensors. I changed the O2 sensor and the engine coolant sensor just to try some process of elimination.... no change so far. Any ideas would be greatly appreciated,,.

bigblue91601

I have this same issue with my Jeep, especially when it gets cold! I found that if you turn the key into the on position (right before you start it up), I have to wait for the check engine light to turn on, on the dash before it’ll actually start up, if I don’t wait for it to turn on, it won’t turn on! I posted on somebody else’s question and somebody said this condition was due to something, just can’t remember what they called it, I’ll look it up and tell you what they said. Try doing what I do and if it doesn’t work then 🤷‍♂️

bigblue91601

This is what i was told,



Right, check fuel pressure. The previous poster sounds like the regulator is shot. Mine does the same thing. You give it the 'poor man's prime' by turning on the key for a couple seconds.