Engine problem during hard accelleration

[tzque]

When I punched my car and hit about 55 60 it starts to make a sound as if it is a backfire in the intake .
I have put in a new fuel pump fuel filter and better gas .Now it does it when I get around 70/80 . I just installed my scan master . What do you think it is and what reading should I check on my scan master to provide more info .I read the similiar thread below so I am going to check my vacuum lines . Please help

 

[Pronto]

Misfire-coil, wires, sparkplugs should be checked or replaced.

 

[RBruton]

Had the same issue

I have the issue, it finally got to the point where it felt like it was only running on 4 cylinders, been doing it for about a year and I couldn't figure it out, changed chips to an old stand by, changed plug wires, plugs, coil pack. When it finally failed it is running rough and able to build boost with in park and thats never happened, we're thinking it may be the VSS sensor that has failed. We're in the process of replacing that, I'll let you know. Couldn't find any vacuum leaks either

 

[GNRick]

Check your TPS volts. You might have a dead spot in the TPS sensor. I couldn't find mine with key on/engine off. But under load when the car was accelerating, it reared its ugly head and caused a backfire.

 

[Chuck Leeper]

Problem happen at/about the same rpm?
Scanmaster readings are?
Valve springs going/gone??
Fuel psi is?

 

[TurboBuRick]

Flat/worn cam?

 

[86GN-862+2]

Mine did the same thing this weekend. It turns out that the fuel pump prime wire near the fuel regulator was hitting ground somehow. Made the engine stumble, backfire and finally killed it. Got it wrapped and problem solved. Hope your fix is that simple. G/L

 

[mikestertwo]

Hope it's not a blown head gasket.