Please Help,

I have a 97 Ford F-150 with approx 115,000 miles. Check Engine light came on. It was running great but it through code P0401. Low Flow to EGR. I replaced the EGR Valve and the DPFE Sensor reset the computer and the light came back on two days later. Took it to the Ford Mechanic and they found the intake manafold was full of carbon build up. They cleaned it and replaced gaskets and the "throttle plate" (?) and gave it back to me. It has a lot more power and alot quicker when punching it to pass. All good news. Now however the idle is rough. It seems to hang around 850 rpm but it jumps quickly to over 1200. All this even if it is warm. Even when the truck is in gear waiting at a light, the idle ramps up and the truck trys to jump. Any help would be appreciated. Please E-mail me!

 

sounds like a leaking intake to me, when the motor is cold start the truck and spray either or carb cleaner around the intake, if it speeds up you found the leak, then you take it back to whomever fixed it and let them deal with it, also try unpluging the throtle posission sensor, notice any change?

 

I posted the first message only hours after picking up the truck from the Ford shop. I turned the screw, that provides the throttle position back, which lowered the idle to between 700 - 750 rpm. This morning I warmed up the truck before going to work, drove aprox 10 miles, and the idle stayed consistantly at 700-750 rpm. Is this normal? It didn't feel anything like it did yesterday. Maybe the new intake and EGR gaskets needed to seat? What do you think?

 

PCM relearning probably

 

LxMan1 sounds right, the motor needs to get to running temp and cool before the pcm will relearn the settings for everything, and since they reset the pcm to clear the codes when you had it fixed this makes sense, 700-800 is normal idle on the 5.4 so sounds like its running fine.

 

It's been a couple days and everything seems to be fine. The idle has stablized. I have a Tritan 4.6. Is the idle the same (700-800)? Thanks for the response on past postings and for future.

 

Yep, It sounds about right.

Jimmy