running problems

[sleeplessinmech]

i have a 87 grand national, recent purchase that was not running right when i bought it. hesitates and stumbles when accelerating thought it may be module or coil, replaced module and the car would not start, thought was bad module so i got another one and the same thing, put old one back on and the car starts. i then bought a second grand national that runs fine, so took module and coil pack off and put it on my first one and the same thing will not run, i am stumped

 

[TexasT]

Aged out vacuum lines. If you touch em and draw back a black mark on your hand, they need replaced. Next would be a stock maf. If it is stock or a stock replacement I doubt it is any good. There is a reason people put a translator and newer style on em. They work.

If you don't have a scan master you need one. Then post up the "numbers" at idle and driving.

After you get the idle figured out a hot wire and new fuel pump is needed.

 

[dynoman]

We need a lot more info about the car , as in any mods it has , any scan tools , scanmaster , powerlogger , aftermarket ECU ...... Check out Vortex buicks trouble shooting tree . Start Trouble Shooting Here . Are you new to Turbo Buicks ? Post up your mods , if any , in your signature to help us help you . Also where about do you live ? Maybe someone near by that can help .
Welcome to the Forum !!

 

[SCOOBY DOO]

Give us the Scanmaster numbers with the engine warmed up in Park. You'll waste a ton of money throwing money at these cars guessing.

 

[Buick Mark]

MAF