marc_41_745

My 88 jeep cherokee starts up and idles fine but when you hit the throttle it dies out and sometimes back fires out of the throttle body. The jeep has been sitting for a year.

marc_41_745

Could the fuel filter be clogged and starving it for fuel?

MtnHermit

I'd suspect the TPS (throttle position sensor).

When you hit the throttle, it gets a lot of air, the TPS needs to signal the computer to add fuel, else the mixture is too lean and won't fire.

Try applying the throttle slowly rather than nail it, does that help?

cruiser54

That, old gas, or a weak fuel pump are possibilities.

marc_41_745

The fuel pump was changed a month before I parked it. I tryed putting new gas in it.

cruiser54

Could be alot of things. Popping through the intake is usually lack of fuel.

How are the plug wires? Rodents been munching on them?

marc_41_745

Wires look good. They were replaced about 6 months before I parked it. I ended up getting a 98 so I was driving it. But now I want my old one back haha

marc_41_745

So I changed my fuel filter and that still didnt help.

cruiser54

Need to do a fuel pressure test. If the pump you installed was Airtex, it could be bad.

marc_41_745

Im not getting good pressure when I turn the key on. When it first starts it has about 35 psi then it drops to zero and the jeep wants to stall out

cruiser54

You need a fuel pump, Marc.

marc_41_745

Changed fuel pump now I have fuel pressure but still have the same problem

cruiser54

What kind of pressure now?

marc_41_745

Well I got it to run. I ran a hot wire to the fuel pump now it runs. It has a small miss but it runs

cruiser54

Ever jump across the fuel pump ballast resistor?