Im currently having some flakey issues with my max.
The car has been down for a couple of weeks and we cannot seem to figure out what could be the cause.
Symptoms are that it has a rough idle under load of accessories.
I can start it up and it will idle fine, but if I leave it running for a while it will eventually just stall on its own.
Now when its idleling if I tap the brakes, the idle drops and becomes rough untill I relase the brakes, if I turn the lights on it does the same. If I turn the AC on it kills the car automaticly. Now when I drove it, it kept shutting off on me. I would have to keep giving it gas at the lights to keep the RPMs up so that it wouldnt die.
It doesnt have a CEL and has not thrown any codes.
So far I have
replaced the IACV with a new unit from the dealer,
replaced the PCV valve
Had the battery tested, and it tested good
replaced the alternator with a good tested one as well
My buddy who currently has it is a mechanic for Infinity and he doesnt seem to know just what it is at the moment either.
He tested the MAF and said it seems fine, he is now thinking it may be the ecu. weve looked for vaccum leaks and havent found any, also have searched the wiring harness for breaks or bad connections and havent found any of those either.
The car was running fine, and out of the blue it started doing this.
Now I am boosted, but I dont think the issue has anything to do with boost.
Any suggestions?
Please, if you dont have logical suggestions, dont ***** the thread up.
Im trying to get this figured out and I dont need posts like clean your TB, because the TB is clean!

 

I would triple check for vaccum leaks again. Sounds to me its definetly that.

Also whats your FP ? Could possible be the fuel pump ?

 

Reading from the gauge its at 40psi in idle.
To me it seems like a vaccum leak as well, but i cannot seem to find it. I will continue to look this weekend.