I have 97 GMC Sierra 2x2 6 cyl truck. The truck will start and sounds great at idle and even runs fine with a little pedal but when you rev it either while in park or driving it floods and boggs down. Any idea what this may be. I know the fuel pumps on these things go often but would this be a fuel pump issue. Thanks for any and all help. Mark

I am having the same problem. This started after I changed the fuel filter.

Thanks in Advance.

Stillman. I'm having my fuel pump changed as I speak I will let you know if that is what caused the problem.

I'd have the fuel pressure tested and check the cpfi unit for a bad press regulator or bad injector poppets, common problem with the Vortech.

My 97 with the5.7 acted like that it was the fuel pump. Funny thing happened with pressure test it had 60 p.s.i but when I tried to accelarate fast it would bog down. I changed the fuel pump it ran normal. I was told it had enough pressure but not enough volume.

So I took my truck to get a diagnos. It gave me EGR sensor and the Air Mass flow. So I replace them and truck is still doing the same. I took it back to the place I did the diagnos and did the diagnos again and it gave 2-4-5-7 pistons are mis firing.
The mechanic said to change the distribiator cap wire's and plug and this should make the truck run normal.

What do you guys think should I do this?

Thanks in Advance.

Try the lowest cost fix first,my truck would idle fine , but when I tried taking off fast it would stumble. I could get to highway speeds if I eased into it.

By the way when it was doing all the stumbling it was the fuel pump. Now I just had a problem with misfire at no 4 and the intake gaskets were bad

By the way when it was doing all the stumbling it was the fuel pump. Now I just had a problem with misfire at no 4 and the intake gaskets were bad

So I took my truck to get a diagnos. It gave me EGR sensor and the Air Mass flow. So I replace them and truck is still doing the same. I took it back to the place I did the diagnos and did the diagnos again and it gave 2-4-5-7 pistons are mis firing.
The mechanic said to change the distribiator cap wire's and plug and this should make the truck run normal.

What do you guys think should I do this?

Thanks in Advance.
Sure let them do this work with a written guarantee that this will fix it, if not you get a refund.

Good idea make them back their diagnosis