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Low boost?


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Something is not right. Do you have a wideband? or a fuel pressure gauge? Start with checking the easy stuff. Reseat the ECU, clean all grounds and contacts. make sure there are no vacuum leaks. Change the plugs and make sure to get NGK plugs. I am assuming this is a stock ZX turbo motor running with no IC and stock electronics.

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Okay I just got done cleaning all electrical, and checked all my vacuum, its running very close to 5psi but when my car shifts(auto) it moves to 6-7 psi but then back down to 5psi a second later... wtf? I changed my plugs last week with ngk's so I know it is not them.

 

I guess i'm gonna try to test my fuel pressure tommorow and see what it is reading. Any more help would be great, I thought boost was suppose to drop during shifts but In this case its opposite..

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Okay I just got done cleaning all electrical, and checked all my vacuum, its running very close to 5psi but when my car shifts(auto) it moves to 6-7 psi but then back down to 5psi a second later... wtf? I changed my plugs last week with ngk's so I know it is not them.

 

I guess i'm gonna try to test my fuel pressure tommorow and see what it is reading. Any more help would be great, I thought boost was suppose to drop during shifts but In this case its opposite..

 

have you checked your throttle linkage? It may not be opening up all the way. I know i experienced this thinking i had a boost problem (5psi), popped my hood and found that there was more throttle to be had.

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have you checked your throttle linkage? It may not be opening up all the way. I know i experienced this thinking i had a boost problem (5psi), popped my hood and found that there was more throttle to be had.

 

Linkage is good, just checked it and tightened it some, no difference there.

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I would look at timing first. I don't know what your timing should be at at idle but have you checked that yet? Even if you were a little lean it won't cause knock unless you are really close to the edge, which you should'nt be running under 7 psi. You running atleast 91 octane?

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sounds like you are off a tooth on the dizzy shaft... if your having to clock it one way all the way in order to get near accurate timing.

 

put the car to TDC on cyl 1 and recheck the orientation of your dizzy shaft w/ the dizzy off... be VERY anal that it's exactly as shown in a FSM. i'm guessing you'll find it's 5-15 degrees off the axis shown in FSM, which means as your timing adjusts when your boosting, the car then goes into a improper curve.

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