slydawg890

Puchased my first performance vehicle, an '04 Mustang Gt (Auto) last week from a dealership. Prior to purchasing, I took it on the highway as fast and as long as I could, put it through the gamut on the city streets, and finally plugged in my OBD scanner...no codes/sensors so I bought it. Last night I noticed a slight hesitation/sputter while cruising at 70mph. Got home, plugged in the OBD and it didnt show any codes/sensors. Started it up and noticed a slight hesitation but smoothed out in a few seconds. Took it back out on the city roads and nothing. Took it on the highway and after about 10 miles, I noticed the sputter again, but it was gone as quickly as it came. Got back on the city roads heading home and it started sputtering again for about 30 sec or so then smoothed out. About 2 miles down the road, I made a right turn and it sputtered, wouldnt accelerate, and then died. Plugged in the OBD and still no codes/sensors. Started it up and drove home just fine. Ive had some experience with my '04 Expy's COPs and this didnt feel like that, plus I would think it would pop a code. Any suggestions are greatly appreciated.

cliffyk

If you just bought it last week then bring it back to the dealer and tell them to fix it and call you when it's done...

amazingrandy1

I agree with cliffyk, but if you dont bring it to the dealer I had a similar problem. I recently replaced my intake because the coolant passage finally blew, so I replaced the intake and road tested the car with no problems. I then sprayed the engine down and washed it, and a very small amount of water got past the coil-plug boot and caused two cylinders to arch out against the heads. It would run fine at certain RPMs, but it was so bad at time that the car stalled until I dried everything out.....Oh, and there were no codes stored or pending in the ESM. Hope this helps.

decipha

check for any vac leaks and/or pcv hose issues, although the no acceleration, thats a tad odd

slydawg890

Was able to obtain the service records from the dealership. Complaint history was roughly the same as I'm experiencing now. In the last 3 months they have replaced all COPs, plugs, fuel pump/gasket/filter, battery, trans flush/fill, and oil/oil filter. Cleaned the IAC and replaced air filter yesterday and it ended up dying more frequently. Today I will be replacing the TPS and cleaning the MAF sensor. Any other suggestions?

slydawg890

Obtained the service records from the dealership. Complaint history has been the same as I'm experiencing now. In the last few months they have replaced all COPs, plugs, fuel pump/gasket/filter, battery, flushed/fill trans fluid, changed oil/filter. I cleaned the IAC and replaced the air filter yesterday and it died on me more frequently. I will be cleaning the MAF sensor and replacing the TPS and PCV today. Without a smoke machine, any suggestion on how to check vac leaks?

slydawg890

Obtained the service records from the dealership. Complaint history has been the same as I'm experiencing now. In the last few months they have replaced all COPs, plugs, fuel pump/gasket/filter, battery, flushed/fill trans fluid, changed oil/filter. I cleaned the IAC and replaced the air filter yesterday and it died on me more frequently. I will be cleaning the MAF sensor and replacing the TPS and PCV today. Without a smoke machine, any suggestion on how to check vac leaks?

96t-bird

I agree with cliffyk. why are you not taking it back to dealer? is the car a AS IS sale? if the dealership repair/replace all those parts. and still could not fix the car, they know the car was a lemon. and should be held reliable for the repairs or replacement of the car.Good luck

mojo2go

That definitely sounds like a cop issue, but there should be a misfire code set if that's the problem. A cheap easy way to test for vacuum leaks is to spray throttle body cleaner around the intake gaskets and anywhere there is vacuum...but be careful!
I had the same issue with my '99 GT and found that the fuel pump inertia switch in the trunk was going bad. Sometimes it was fine, and other times I'd get the sputtering. replaced that switch and solved the problem.