[Lous6t4gto]

Is there any way to "TEST" a Ignition control module on a 1999 grand Prix 3800SC ? (on of off the car ) ?? car starts and idles. when trying to drive, even slowly it has a "Miss". hit the throttle and it falls on it's face ! total BOG/ backfire through Throttle body, until I let off the gas pedal. It already has a New TPS, 3 coils,Plug wires, delco plugs @.045. Help .
Thanks
I really don't want to buy a new "Wire harness" if I don't need one.
It's a '99 3800SC in a 1987 Fiero GT. ( It did run GREAT until put in storage for about 10 months)

 

[MikeK]

It ran great in the Fiero before you stored it?
If not, your fuel pump probably can't supply the volume of fuel needed.

Plenty of diagnostics here:
Part 1 -GM 3.8L Index of Articles
Page 3 has ICM testing

 

[mr goodwrench]

Laying down on hard accel or an INTAKE BACKFIRE are classic symptoms of "lack of fuel". Mike is correct in the fuel pump issue. You should check for a plugged fuel filter also. Do thst before changing the pump..

Jake