ernierob130

It was -2 this morning, it's a 5.0 and 5 star tunned for over a year, and had no problem.. Went to start it up this morning and left it warm up and it didn't sound right. Went back Out and big wrench was on the screen and it wasn't idling right. I turned it off and back on, it struggled to start and then it started and ran fine and I went to work... Think I have a issue or just blame it on the cold weather

Madorski

I had a similar issue just before New Years. Truck went in to limp home and I actually ran it down to the local dealer.

Mine was a IAT sensor mismatch - one side thought it was -50C and the other side thought it was +30C, so it got confused. ECM / PCM reflash for me, but this was in the EB and non-tuned.

I suspect it was that I had it parked in a heated shop for a day or two and then went out.

mechanicboy

Reset the computer. I have a weird issue within the first few minutes of starting but after changing tunes it went away. It could also be the fuel you are getting as there's a larger than normal amount of butane in the fuel supply recently. A few blown mustangs have lost their engines recently do to poor quality fuel and cold weather.

ernierob130

Stock when I warm up it revs up real high and levels it self off, with the tune it doesn't really rev up much on warm up.. Might have to ask mike at 5 star