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Help! Loping GT

BlackNRedGT

BlackNRedGT

New member
So I have a 1999 grand prix GT and It has a few problems. I get real crummy gas mileage and it lopes all the time. When it's cold it runs fine but as it heats up it lopes after touching the gas a few times before it fines it's idle. I've thought vacuum leaks, MAF, or fuel pressure regulator,but I don't know. Anyone have some advice?
 


Unplug the MAF...if that changes anything then you need a new one.

Vacuum leak...spray carb cleaner around the motor when its running...if the idle changes then you've found your vacuum leak.
 


Ok...so then the MAF is good...check for a vacuum leak with some carb cleaner while its running...do you have any check engine lights?
 
I will go get some a look around with that

And yes I do I scanned it and It came back as mass volume air low(or something like that cant remember fOr sure) and running lean in bank 1
 


Anything most of the time bank one lean is 99.999999999999999% a vacuum leak...most of the time your factory lines and rubber "T" fittings around shot around the fuel rail, throttle body, lower intake manifold, upper intake...etc.
 
Update*
I sprayed with carb cleaner and found a leak. I replaced the vacuum fittings and t fittings. Turned the car on and it continued to lope>:( I then scanned the car again and had two different codes. I musta fixed the leak but now the codes both say MAF is bad... So new MAF?
 


i kinda have the same problem.......

when i turn the car off, you hear woosh sound..?? is that a vac leak???
 
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