GMC Jimmy 2003 Misfire Question?

[Brad Buchanan]

I've had misfire and hesitation while driving. So far I've changed spark plugs and wires, distributor cap and rotor, fuel filter. The problem has continued, the last thing I can think it could be is the fuel pump. My first question is could it be the fuel pump? Second question is what other things could it be?

 

[Molson02536]

I've had misfire and hesitation while driving. So far I've changed spark plugs and wires, distributor cap and rotor, fuel filter. The problem has continued, the last thing I can think it could be is the fuel pump. My first question is could it be the fuel pump? Second question is what other things could it be?

Start with getting your Jimmy scanned for any DTC codes. It could be as simple as cleaning your MAF sensor or replacing your TPS.

Keep us posted and also check your fuel pressure at the shredder valve. You should have 62-65 PSI when engine is at start up and should drop about 5 PSI when engine running. Anything less will give you issues that you have described.

Good luck and post back soon.