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Discussion Starter · #1 ·
This just started yesterday I normally run 20 lbs of boost. Then after driving around a while it started spiking and droping to around 17.5 lbs, and does'nt pull worth a crap. It does'nt quickly drop down to 14inHg either like normal. When I let off the gas it will slowly go down to about 2inHg then after idling for a few minutes it will drop down to about 10inHg only after idling for about 10 minutes did it drop down to about the normal 14inHg. Then when the car shuts off instead of the gauge returning to zero quickly, it very slowly returns to zero. The car has no mods other than a Greddy type s BOV with the spring mod. But I'm pretty sure it's not it, because it's been on there a while with no problems and the upper valve is tight and also has teflon tape, and all the other connections are sound. Thanks for any help.
 

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Joe_Halt said:
This just started yesterday I normally run 20 lbs of boost. Then after driving around a while it started spiking and droping to around 17.5 lbs, and does'nt pull worth a crap.
It could be the ECU holding back boost/timing due to higher intake temperatures or low octane fuel.

Joe_Halt said:
It does'nt quickly drop down to 14inHg either like normal. When I let off the gas it will slowly go down to about 2inHg then after idling for a few minutes it will drop down to about 10inHg only after idling for about 10 minutes did it drop down to about the normal 14inHg. Then when the car shuts off instead of the gauge returning to zero quickly, it very slowly returns to zero.
Kink in a vacuum line somewhere... :confused:
It's hard to diagnose a problem online. Hopefully someone had the same problem and can post their solution.
 

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Discussion Starter · #3 ·
OK I found a kink in the vacuum line where it comes out of the gauge and fixed it the gauge is good now. But I still have a spike. It will hit 20 in 3rd and 4th, but 1st and 2nd don't pull so good. Could that kink somehow have caused this? or affected the ECU?
 

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Joe_Halt said:
OK I found a kink in the vacuum line where it comes out of the gauge and fixed it the gauge is good now. But I still have a spike. It will hit 20 in 3rd and 4th, but 1st and 2nd don't pull so good. Could that kink somehow have caused this? or affected the ECU?
This is normal behavior for a stock car, you will not hit full boost in 1st or 2nd gear, only in 3rd and up.

Keith
 
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