problems...can somebody help?

[asrnj77]

So after a thorough warmup I start driving down the highway in moderate traffic, as I'm driving I notice that under acceleration I hear little burps. As I'm nearing home I give it some gas maybe a little more than half throttle and she starts stumbling bad...basically wanted to stall out and die but I give little bursts of throttle to limp home. At the light I had to keep it in neutral because it would have stalled in drive. The scanmaster showed no knock but the 02 was flashing between 170-270. When I got home I put it in park and 02 went to 678 and then it was about to stall again so I cut it off. This experience reminded me when I blew a coupler on my other turbo car but I checked and didn't see any busted couplers or blown hoses. Is there anything else I should be checking? What am I missing? Thanks

 

[bmackinnon]

fuel pump dying? sure what it sounds like.... need to check fuel pressure... while/after driving.... pump might be ok at startup, and then start falling off when it gets hot...

 

[RUQWKNF27]

Might also be bad oxygen sensor.

 

[stagemonster]

Check all your grounds.

 

[Underboost]

How long have you had the zo6 sensor with conversion harness? Do you still have your stock MAF setup?

The XP Pump is a great pump I say better than the Walbro 340 but you never know. Do you hear the the pump energize for 5 seconds when you turn the ignition on.

 

[asrnj77]

I'm starting to think this may be electrical. Last night I had problems with the alarm and then when I tilted the steering wheel it shut off completely. I raised the steering wheel back up and it seemed to be ok. I can't see any damaged wires but it certainly seems like it could be related.

 

[Underboost]

I'm starting to think this may be electrical. Last night I had problems with the alarm and then when I tilted the steering wheel it shut off completely. I raised the steering wheel back up and it seemed to be ok. I can't see any damaged wires but it certainly seems like it could be related.

Ignition wires could be getting pulled some how? You should get down under there with a flash light and move the steering wheel up and down just to see whats going with the wires.

 

[GNRick]

Is your tilt wheel lose? My mechanic repaired mine because he said eventually I would have problems like you describe. At first I was thinking your MAF took a dump.

 

[asrnj77]

fuel pump dying? sure what it sounds like.... need to check fuel pressure... while/after driving.... pump might be ok at startup, and then start falling off when it gets hot...

You may be onto something. So we checked some diagnostics today and although wires were all over the place under the dash it didn't seem to affect much other than the gauge lights. When we tried to put a fuel pressure gauge on the rail we found that all the pump was putting out was air. The gauge was showing 3/4 before it went crazy and I can hear fuel sloshing around when I shake the trunk but I might just try adding more just to rule that out. I can hear the pump energize and it seems to be pumping but no fuel is getting to the motor anymore. This seems to be the most pressing issue right now

ECM and chips were checked and appear to be fine

 

[bmackinnon]

yup... being as how the fuel system is a recirculating-type system with constant return (and thus purge) flow, there should be ZERO air in the lines... and fuel pressure should be rock steady... looks like this is the avenue you need to pursue.... if you find good fuel pressure at idle, attach a hose to the fp gage you are using and tape it to the windshield so you can see it while driving to ensure pressure is rising exactly 1:1 with boost above base (vac. line off the regulator) pressure... ie. 43 psi (base) + 18 psi boost = 61 psi fuel pressure at wot... (substitute your numbers as appropriate)...

 

[asrnj77]

Ok so I got the fp gauge on there. It was showing 41lbs and then would quickly drop to around 20lbs and when turned off it would drop pretty quick too. Turned up the fp and it will drive around now but its just a temp fix. The fp does rise with boost but seems to be dropping too quickly. Could this just be a new regulator or do I need a new pump? Since the fuel gauge isn't working right anyways does that mean I need a new hanger? Could the hanger/sending unit be part of the problem?

 

[charlief1]

I have seen the hose conecting the pump to the hanger deteriorate and cause something like this. Hope it helps.