So I'm driving home from work last night with the windows down. I come upto some traffic on the highway so I roll my windows up a crank up the A/C. Hot air starts blowing. I give it a minute and it still isn't cooling down. I shut the A/C off and try again, still only hot air. I put the windows back down and proceed home.

This morning I tried again, still only hot air and this time the instrument panel showed a check engine light. I head straight to he dealer hoping it's not a big deal, boy was I wrong. Apparently with these cars, the A/C unit shuts down when the car is at WOT (I did not know this). So apparently my car thinks its going lights out all the time now. The tech also told me the computer was throwing 8 error codes related to the variable cam timing, and exhaust sensors, and that the computer was telling the engine to cycle between rich and lean constantly.

Long story short: the dealer is ordering a new ecu and that it would take a week or so to come in due to the holiday. I asked if I could have the car in the mean time and they said that they would not recommend driving it anywhere.

My only mods are listed in my sig (good thing I haven't gotten a custom tune yet!) and hopefully its not because of one of them. Just thought I would share the bad news

 

Hmmm, could it be the high-flow cats I wonder? Naaaa, nobody else has had problems.

Let us know how it turns out.

 

After driving around town in my loaner Ford Focus for 5 days now, I have really been missing my Mustang! Salvation came today though as they called and said that it was indeed a bad PCM (same as an ecu?). They replaced the part and recharged the ac (which also had an open fuse) and all is good.

I am not sure why after on 6000 miles the pcm went bad, but I am glad I had not paid for a custom tune yet! This may cause me to wait even longer before getting one. Not a bad thing since 93 octane is currently $3.45 around here. Thanks!

 

Craig - And no they never mentioned anything about the hi-flows.

 

There was a blown fuse in the A/C? That's odd. Or did they replace something related to that plus the PCM? And yes, the PCM is the same as the ECU -- PCM is just the new mandated term (to eliminate confusion between manufacturers).

Good to here you're back on the road. Ha, a focus, must have been rough.

 

I would not worry about the High flows.I have no cats and have had no problems for well over two months now.Did not even shut backs off either.