Madman1

This is gonna be a little long sorry but I wanted to give you guys as much info as possible.
Pulled motor to replace rear main didn't touch the timing chain or the heads. Put the motor back in and all the car did was backfire extremely loud, inconsistent spark, fuel pressure at 15-20 psi.
So we have checked plugs, wires, all of the connections to all of the components opti, coil, and ignition module. Checked voltages from the computer to the components checked out ok. Replaced the coil, the ignition module, and took the original opti and put it back on the car in place of the new one both worked fine before. Replaced the fuel pump (Walbro 255 Intank) and fuel filter. Pressure is still at 15-20 psi. And put on 58mm Throttle Body.
Car is trying to start spitters and sputters and backfires out the exhaust and occasionally out the intake and wants to run. But it won't. Getting spark and fuel. Just seems out of time.
So here are my questions. Are both optis bad? Compression problem? Fuel delivery problem? Or is it a wiring problem?
Any help would be appreciated. Thanks

badass383

The plug wires are not hooked to the right cylinders or you have a bad connection (like a bent pin) to something you disconnected and reconnected.

Got to be if it worked fine before you pulled it.

$hawn

That fuel pressure is low as well. With the key in the on position it should be 41-47. With the engine running at idle pressure should decrease by about 3-10psi. with the vacuum line off it should be 43.5 + or - 2.5psi. Is the pressure bledding off when you check?

Madman1

Thanks for replying. Before this mess the car ran on 20-25 at idle with the Accel Fuel Pressure Regulator and the Accel Fuel Pressure guage. I know the guage is right we checked it, the pressure is just wrong. So we replaced the pump with the Walbro 255 in tank pump and a new filter and I am still getting the same pressure. Is the regulator bad? I don't think we messed up the install the pump runs. The Accel Ignition has been blowing the ignition fuse in the relay box under the hood whenever I hook it up but not the fuse for the Accel Ignition so I have been running factory, forgot that in original post. I'll check the pins on the connections today. Anymore ideas let me know.

Thanks

Madman1

TTT

94F1Z28

Well i agree the fuel pressure is low,it should be atleast 35psi with the key on.Also recheck that all the plug wires are on properly and in the right order on the opti,take your time to be sure.

joeSS97

I suspect the regulator.

Madman1

TTT......

Madman1

anybody else...TTT