Question about boost spike then only holding about 11psi.
03-06-2009, 05:38 AM
#1
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Question about boost spike then only holding about 11psi.
I figured I would ask you guys.
I am helping a friend with his 2004 Gti 1.8T today
His problem. it spikes up to 20 but then falls almost as fast then holds at 11 psi and then slowy drops off from there.
The car. APR fully loaded ECU, APR exhaust turbo back, R1 DV, and we switched out the stock N75 with an APR race one in September. We switched it b/c it was doing basically the same thing but less PSI with the stock one.
When we switched out the N75 it seemed to help a little bit (3 weeks-ish) but has since seemed to go back. When we put it in it held more boost for longer. But that was short lived.
I have already checked for boost leaks and there was one small one we fixed by the DV.
I checked all hoses and all were fine.
Should I change out the N75 today and put stock back in? could that be it?
I was also thinking would a bad wastegate/line or something cause this? Stock KO3 with about 45,000
Another symptom not sure if its related or not but sometimes at low/mid rpm when you hit the throttle there is a pause and then it goes. Almost feels like a misfire or slipping clutch that kind of feeling. We tested the clutch in a high gear low rpm and it seemed fine. No codes and we have changed out the plugs and it also has all new coil packs.
TIA
I am helping a friend with his 2004 Gti 1.8T today
His problem. it spikes up to 20 but then falls almost as fast then holds at 11 psi and then slowy drops off from there.
The car. APR fully loaded ECU, APR exhaust turbo back, R1 DV, and we switched out the stock N75 with an APR race one in September. We switched it b/c it was doing basically the same thing but less PSI with the stock one.
When we switched out the N75 it seemed to help a little bit (3 weeks-ish) but has since seemed to go back. When we put it in it held more boost for longer. But that was short lived.
I have already checked for boost leaks and there was one small one we fixed by the DV.
I checked all hoses and all were fine.
Should I change out the N75 today and put stock back in? could that be it?
I was also thinking would a bad wastegate/line or something cause this? Stock KO3 with about 45,000
Another symptom not sure if its related or not but sometimes at low/mid rpm when you hit the throttle there is a pause and then it goes. Almost feels like a misfire or slipping clutch that kind of feeling. We tested the clutch in a high gear low rpm and it seemed fine. No codes and we have changed out the plugs and it also has all new coil packs.
TIA
03-06-2009, 06:35 AM
#7
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FWIW, usually a torn WG line would cause boost devaition. Big sweeps or spikes.
I would try unplugging the MAF.
I had a similiar problem during stage 1 with GIAC. It ended up being the ECT.
I had a similiar problem during stage 1 with GIAC. It ended up being the ECT.
