fast idle when cold
Registered User
Joined: Jun 2012
Posts: 9
Likes: 0
I have an 08 mega cab with a 5.7 hemi. My problem is when I start it cold it revs up to 1500 rpm and takes about a minute and a half to idle down after that you can shut the truck off and restart it and it will do the same thing until warmed up. You can also shift it while still at the higher rpms (which i dont like to do) and go back to neutral or park and the rpms are low, but if you turn the engine off and restart the same problem until the engine is warm. I took it to the dealer because it is still under factory warranty and they said there were no computer or sensor problems and blame it on ethanol and varnish build up on the throttle plates. They recommend cleaning the fuel rails, throttle plates and air intake system for $230. I have cleaned the mass air flow sensor and throttle plate my self but that did not help. Does anyone have any ideas.
i baugt a DSP and shut that high idle off so when it starts it will rev and drop to idle speed in about 5 to 10 sec rather than 1min
