I have a '99 Grand Marquis recently it started have problems at idle. Sometimes it idles but it feels like it is idling below its normal idle speed. When driving it doesn't have a problem at any speed, however, occasionally when cornering it will die. The check engine light has not come on (other than the normal times when starting or restarting). I had the codes checked anyway and as I expected I set a code of P1507 because I have been keeping my foot on the accelerator to keep it from dieing at idle. Any suggestions would be greatly appreciated.
On Sun, 11 Sep 2005 12:07:17 -0400, "lmcsween"
IT sounds like tha IAC is dirty. Many times they can be cleaned and reinstalled after soaking in throttle body cleaner for a while followed by a good spray dousing. While you are at it, it would be a good idea to clean the MAF sensor and the EGR ports in the manifold. The IAC will not normally set a fault code just because it is dirty. It can also cause hard cold starts and no high idle when cold as it should be.
Almost 100% sure. May be crapped up, may be shot. Just had exact same thing last week on my Vette. Ran rough for a long time before it gave out. Pintle all carboned up.