7 psi+...........

[SideSlip]

My stock '87 GN was out for the first time this year........."spring cleaning" was followed to the letter. Above 7 psi all I get is a huge "POP" or a muffled bang from under the hood and the boost drops off instantly, like a rock........right into vacume. Boost will not rise above 7 psi, even when I sneak the boost up real slow........it just stumbles and falls off. Fuel pressure never falls below 35 psi.... new plugs gapped at .35 Runs fine otherwise............ Whats up??????

 

[Red Regal T]

GOOD CHANCE IT'S A COILPAK OR IGNITION MODULE PROBLEM

 

[TurboRyan]

Originally posted by Red Regal T
GOOD CHANCE IT'S A COILPAK OR IGNITION MODULE PROBLEM

I would have to aggree. I had a VERY similar situation and it turned out to be a bad coil pack. Check it with an ohm meter and see what you get. If I remember correctly, you put the test leads on the two posts of each of the three coils one at a time and you should get between 11,000 and 13,000. Hope this helps.

Ryan