My Mustang is an '05 V6 completely stock and has been having idle problems recently. When this problem occurs, the idle drops down to 500 RPM and fights to stay running. Usually this happens as I am slowing down at an intersection or coming to a stop, however it is not a consistent problem and seems to happen only once to twice a week. If it dies, it still fights to stay running when I restart, usually causing me to give it some gas to keep it running if I'm at a stop light. I have also noticed that if it can keep running and I put the accelerator down while driving and gun it for a few seconds that it will idle normally the next time I come to a stop.

I have searched forums and found posts by other owners who have had similar problems, but have yet to find anyone who has found a solution to the problem. I know about the TSB about fuel pump problems, but I this seems to be different issue. If anyone has any information or advice it would be greatly appreciated.

 

Complete random shot, but check + clean the air filter, perhaps not getting enough air? Or else a vaccume leak maybe.

 

Sounds like classic sytems of a stuck EGR valve. Carbon particles can cause the valve to stick open and when you "gun" it the particle is blown through and corrects the problem until another particle gets caught. This happening at least weekly shoud have thrown a trouble code. I dont suppose your check engine light is on is it?

 

Nope, check engine light has never come on. Do trouble codes get logged without the light coming on?

 

dealer...

 

no if it pulls a trouble code your light will definately come on, still could be a sticky egr valve though, I suggest dealer

 

I had this exact same problem a few weeks ago. I came to the conclusion (after reading this possibility on another post) that it may have been a bad tank of gas or water in the gas because it started acting up right after I fueled up and hasn't happened since I used up that tank. I found this hard to believe, didn't think you could get a "bad" tank of gas. But until it acts funny again, that's what I'm going with.

 

1) Fuel filter.....2) fuel filter.....3) Probably the Fuel Filter.....And did I mention the Fuel filter?

 

I changed the fuel filter on mine and it still acted up