3.0 has wicked engine flare on cold starts
2004 Ford Ranger 3.0 Gas V6
I have this really annoying issue going on with my truck. On the initial cold start in the morning the idle will flare up to 2k RPMs and stay there. I had this going on in the fall and thought I fixed it but it's only started doing it since the outside temperature is above 40+ degrees.
In the fall of 2011 I replaced the Idle air control valve, cleaned the maf sensor, and changed the oil/filter. The issue seemed to go away. Now fast forward to last week before I changed my oil it flared up to 2k RPMs twice and I thought I hit the gas pedal both times. However, after the oil change it has been doing it every single time but it has also been warm like the 2 times it did it prior to the oil change. I checked vacuum lines and couldn't find any leaks. I believe if that was the case it would do it constantly.
Truck completely cold - it will rev up to 2k RPMs and hang there for a minute. Then the idle will back down to 1500 and sit there until the engine is warm. It's hell on the the brakes. Once the truck is warmed up (in open loop), it drives perfectly and the idles at 750rpms.
Truck Engine History
45k Shorty Headers added
45k Coolant Flush
50k Motorcraft spark plugs and wires
50k PCV changed
Engine flare started happening around 589xxk miles
59k Idle air control valve replaced, maf cleaned, and air filter changed
Motorcraft Oil Filter and Mobile 1 Synthetic Changed every 3k miles
Engine Coolant Temperature sensor? I'm stumped.
Last edited by Hillyard; 03-02-2012 at 06:53 AM.