duffman668

Hey everyone. Hope all is well with you all. I have been having this weird issue with my car these last few months and was just wanting some ideas of what could be wrong, or if someone has experienced something similar, what the problem could be.

Car is a 2007 GT 4.6l

So I have been having this issues where when I am in 5th gear on the highway, the car will act as if it is backfiring or missing when I give it any kind of gas. It will accelerate, but it sure acts like doesn't want to. It doesn't seem to matter what RPM I am at. I don't have this issue in any other gear. I also don't have this issue if I am in 5th gear while the car is still warming up. It acts fine then. It only seems to act up once it hits its normal temperature.

I have re-tuned, just to make sure something wasn't weird there. I cleaned and re-oiled the air filter, cleaned the TB, cleaned the MAF sensor, made sure there wasn't an exhaust leak or vacuum leak. I'm about to replace the spark plugs and injectors, just for routine maintenance, but I don't think that will help this issue. I have no CEL on at all. The transmission seems okay, it shifts easily into all gears, doesn't clank, grind or pop out. Granted that doesn't mean there isn't underlying issues. Anyway, any help is much appreciated. Thanks in advance!

danzcool

There was a TSB for 2005-2006 about hesitation on acceleration and cruising at a steady state for a while, it was a faulty fuel pump. Not sure since yours is a 2007 but if the fuel pump is bad or going bad it could have the same symptom.
TSB 06-9-9