My gfs 99 Xj hesitates when u first take off, it backfires and just falls in its face then Takes off.. Had a tune up still doing it? Any ideas? Fuel related? Thanks butch.

 

Backfiring is usually related to an imbalance in fuel/air ratio.

1. Verify fuel pressure. With a gauge. A 97 should have 49 psi, plus or minus 5 psi. Many parts stores will rent you a gauge inexpensively.

2. Test your MAP sensor. Very important input for fuel/air ratio. Be sure vacuum line leading to it is pulling good vacuum.

3. Are the oxygen sensors original? Replace them. With NTK sensors, which are the OEM sensor for that year.

There certainly are other possibilities, but I'd start with the above things. In that order. Here is a link to similar advice.

http://www.2carpros.com/articles/wha...ngine-backfire

Good luck and keep us updated!

 

Thanks! Ill check in to it more

 

Kickdown cable intact?

 

Yes. Why would that cuz back fire?

 

It wouldn't. Tjwalker's list is a great one. Start there and let us know

 

Yea didn't think so, will do.

 

No it wouldnt cause a backfire but it could cause a hesitation and then a quick jump up, I also agree with tj walker