Replace the idle air control valve , takes about 15 minutes to do and will save you a lot of pain and suffering . It will be the best 45.00 dollars you ever spent. When idle has returned to normal ? also check for vacuum leaks at all controls even at vac. solenoids. Hope this helps!
AnswerThis question is from me. :-)After the engine server soon light on, I got P1506 error code . It cuased by "Idle Air Contol Overspeed Error"
The general recommend is to clear TB and check the IAC valve.
I clear the TB and check the IAC valve and loose the battery's negative terminal for half hour, then connected it and start the car let the PCM re-learning. (See pic1: http://i20.Photobucket.com/albumsb233taurusprojectpic1.jpg and pic4: http://i20.photobucket.com/albumsb233taurusprojectpic4.jpg )
But the Idle speed is around 1100 --1200 RPM. and the engine server soon light came back again.
I think the clear&check does not work.
This symptos is appear after I change it's HG. I do remember one special termial like a sense that I did not know where it should go( See pic 1: http://i20.photobucket.com/albumsb233taurusprojectpic1.jpg and pis 2: http://i20.photobucket.com/albumsb233taurusprojectpic2.jpg and pic 3: http://i20.photobucket.com/albumsb233taurusprojectpic3.jpg and pic 5: http://i20.photobucket.com/albumsb233taurusprojectpic5.jpg ).
Who know what this special part name and what function it perferm and where it should to be connected?
Anybody has any idea?
Thanks a lot for any input.
New Answer from waitingroom:
If it is not the IAC, check for vacuum leaks. Check the length of the vacuum hoses and inspect for cracks/holes. Especially check the pcv valve/hose. Basically unmetered air is coming in and the IAC can not compensate for it.
Answer from yopw11pw
I just had this problem with my 2001 Ford Windstar 3.8L error code P1506. After running the full spectrum of the Ford flow chart & any ideas I could gather from forums, I did what my dad taught me go back to the basics. The part for the fix was $8.00 & less than 10 minutes. If you look at the front of the engine there is a little black box, it is called an IMRC accuator, there 2 rods coming off of it, 1 to the front bank & 1 to the rear bank. A bushing holds the rod into the IMRC. If the bushing breaks the rod falls out. That is how I fixed my problem.
P1506 - Idle Air Control System At Adaptive ClipCheck for vacuum leaks and clean the throttle body, maybe check the iat and maf sensors.
Trouble code P1506 means: Idle Air Control Overspeed Error
Trouble code P1506 means: Idle Air Control Overspeed Error
Idle Air Control Overspeed Error
That code is an idle air control overspeed error. It means that the engine idle is out of factory specification. Sometimes the Idle Air Control may have carbon built up so clean it and if that does not fix it, replace it.
P.o.s.
Trouble code P1506 means: Idle Air Control Overspeed Error
Trouble code P1506 means: Idle Air Control Overspeed Error
Answer I have a 02 ford escape, and it is doing the same thing your ford escort doing.( overspeed error.) well anyway I was told it is a faulty vaccum harness tube assemby. haven't tried it yet, but thats on the list. cause I've tried everything.Replace the IAC valve.,Well, no disrespect but that IS WRONG. I am currently having this issue myself. I have replaced the IAC, AND the ECM (or some call it the PCM). Guess what? STILL SAYS IAC overspeed error!!!!! Could be anything from a bad head gasket to a vacuum leak.
Error code P1506 is for the idle air control overspeed. Remove the idle air control valve and clean it with carburetor cleaner and check for vacuum leaks. If the problem persists change the valve.
Trouble code P1507 means: Idle air control (IAC) underspeed error
Trouble code P0171 means: System too lean (bank 1)