Hey guys! So I've had my new mustang for a month ish (07 GT with 92k). I recently installed a JLT2 CAI, pypes Orx, and had a mechanic friend tune it with a hand held. Right after the tune the car ran find (about 2-3 weeks 400-500 miles ago).
Now, the car misfires around 1750-2250 RPM, there's a HUGE power loss, you can smell extra gas, the car sounds terrible, and outright refuses to accelerate. Happens at highway speeds and cruising around town.
On cold starts the RPM dip under the minimum rpm line and then jumps up to 2000+ rpm until it drops to around 1200 a minute or so later.
My mechanic friend also did not turn off the rear O2 sensors when he did the tune, instead he said to install spark plug non foulers on the rear sensors.
Could this be spark plugs? COPS? A bad tune? I'm at a loss! I already cleaned the MAF and the air filter.
Any ideas citizens of NYM? Thanks for all of your opinions and happy 4th!
Edit: the 2 times this happened on the highway I got the blinking CEL for random misfire
Now, the car misfires around 1750-2250 RPM, there's a HUGE power loss, you can smell extra gas, the car sounds terrible, and outright refuses to accelerate. Happens at highway speeds and cruising around town.
On cold starts the RPM dip under the minimum rpm line and then jumps up to 2000+ rpm until it drops to around 1200 a minute or so later.
My mechanic friend also did not turn off the rear O2 sensors when he did the tune, instead he said to install spark plug non foulers on the rear sensors.
Could this be spark plugs? COPS? A bad tune? I'm at a loss! I already cleaned the MAF and the air filter.
Any ideas citizens of NYM? Thanks for all of your opinions and happy 4th!
Edit: the 2 times this happened on the highway I got the blinking CEL for random misfire
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