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Discussion Starter · #1 ·
I have an '89 SPG (so it is running LH 2.4). Recently at full boost (16-18PSI) the car seems to stutter. It loses power for a second almost like it's missing. Yet this only happens at full throttle and high levels of boost. I am running the Swedish Dynamics Red fuel chip (unclear if it deactivates overboost). My first guess is that it is the overboost control through the ECU so i hooked up some leads to the fuel pump fuse yet, there is no voltage loss across this when this happens. Could it be that the voltage drops and comes back too fast for my multi-meter to pick up? Or would you think the problem is most likely ignition related. Thanks

Sam-
 

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Discussion Starter · #3 ·
i would agree with you on the dying fuel pump if it weren't so quick and dramatic, it is obviously happening on/off on/off it feels like some kind of control system yet my experiment with the voltmeter makes me think otherwise. i am at a loss. perhaps i will put a resistor in the AMM signal wire and just see if that fixes it, anyone remember what a good ohm range is, i think i heard experiment with 25-75ohm resistors?
 

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check if there is a move in the temp gauge at high boost when it happen. if yes, it can be a leaking head gasket...or maybe a leaking rings at high boost or misfiring.
Do u run an apc or not ?
 

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Discussion Starter · #5 ·
yeah i run APC, i think i will do another run with a voltmeter and see if a more sensitive one will pick anything up....
 

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Discussion Starter · #6 ·
oh yes and no movement on temp gauge, sorry forgot to answer that question, has anyone else out there hit overboost on LH 2.4 and can comment on whether it is an off/on off/on stutter sort of thing, or a face hit the steering wheel apprupt loss of power?
 

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Discussion Starter · #7 ·
verified that it is in fact overboost by running a hot lead to fuel pump fuse location...case closed, now to figure out a new way to bypass it...
 
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