S5 Turbo Fuel Issues

JL1RX7 · 09-04-2016, 12:26 PM

Sorry should have made that more clear, when you put the jumper in the yellow connector, the fuel pump runs like it should. Now even leaving that jumper in there the car starts for a second then dies.

I agree with you on the AFM. But putting a known good one should have made that go away. But it didn't. I don't have a spare turbo ECU to swap that out to cross that off the list.

Pete haven't pulled those yet. Trying everything else before I did that. Going to the store to buy new hose clamps before I dive down that rabbit hole.

vrracing · 09-04-2016, 01:00 PM

Have you put a fuel pressure gauge on the system?

JL1RX7 · 09-04-2016, 05:48 PM

I don't have a gauge yet for that. Otherwise I would have. I have all kinds of gauges to measure air volume, but not fluid pressure or volume.

Pete_89T2 · 09-04-2016, 07:02 PM

Quote:

Originally Posted by JL1RX7

Sorry should have made that more clear, when you put the jumper in the yellow connector, the fuel pump runs like it should. Now even leaving that jumper in there the car starts for a second then dies.

I agree with you on the AFM. But putting a known good one should have made that go away. But it didn't. I don't have a spare turbo ECU to swap that out to cross that off the list.

^It should have unless there's a open circuit in the harness wiring somewhere between the AFM safety switch and the ECU. Swapping out a good AFM in that case wouldn't isolate that problem.

JL1RX7 · 09-04-2016, 08:52 PM

I would like to agree, but unless the break is on the injectors then everything else works. All relays have correct voltages. If there was a broken wire, one wouldn't. I haven't gone all crazy and rang out each wire in the circuit. But if it ran before changing the pump, then the only common would be the pump. Not the wiring. This doesn't mean that old wiring couldn't be the culprit. This car is so close to factory I wouldn't think this. It spent most of its life in a garage with some climate control.

Almost nothing is dry rotted or broken. Even the foam around the radiator was is reasonable shape. It didn't crumble in my fingers. To give you an idea. The foam inside the door cards was in good shape. Only in bad thing on the car is the speakers. They rotted out. Which for its age isn't a big deal.

I am leaning bad ground somewhere. When I started cleaning a few it would at least try to start for a second, better than acting like its flooded out.

Tomorrow I will change the fuel filter and check voltages t the injectors. Once I check those that should tell me what's wrong.

09-04-2016, 12:26 PM	#1
JL1RX7 Rotary Fanatic Join Date: Feb 2008 Location: Front Royal, VA Posts: 487 Rep Power: 18	Sorry should have made that more clear, when you put the jumper in the yellow connector, the fuel pump runs like it should. Now even leaving that jumper in there the car starts for a second then dies. I agree with you on the AFM. But putting a known good one should have made that go away. But it didn't. I don't have a spare turbo ECU to swap that out to cross that off the list. Pete haven't pulled those yet. Trying everything else before I did that. Going to the store to buy new hose clamps before I dive down that rabbit hole. Last edited by JL1RX7; 09-04-2016 at 12:31 PM.

09-04-2016, 01:00 PM	#2
vrracing Rotating Assembly Join Date: Oct 2008 Location: TX Posts: 102 Rep Power: 17	Have you put a fuel pressure gauge on the system? __________________ 90 S5 Vert. JDM Tii with BNR Stage1 turbo. Pineapple Racing street port. Bonez cat-forward. Corksport cat-back with Vibrant UltraQuiet resonator. RTek 2 wZeitronix w/b. HKS EBC. Vis CF Tii hood. 3000GT wing. Ground Control coilover kit with KYB AGX shocks. Red and Black leather RX8 seats. Corksport Odura lip & bumper caps, OEM Tii skirts

09-04-2016, 05:48 PM	#3
JL1RX7 Rotary Fanatic Join Date: Feb 2008 Location: Front Royal, VA Posts: 487 Rep Power: 18	I don't have a gauge yet for that. Otherwise I would have. I have all kinds of gauges to measure air volume, but not fluid pressure or volume.

09-04-2016, 08:52 PM	#5
JL1RX7 Rotary Fanatic Join Date: Feb 2008 Location: Front Royal, VA Posts: 487 Rep Power: 18	I would like to agree, but unless the break is on the injectors then everything else works. All relays have correct voltages. If there was a broken wire, one wouldn't. I haven't gone all crazy and rang out each wire in the circuit. But if it ran before changing the pump, then the only common would be the pump. Not the wiring. This doesn't mean that old wiring couldn't be the culprit. This car is so close to factory I wouldn't think this. It spent most of its life in a garage with some climate control. Almost nothing is dry rotted or broken. Even the foam around the radiator was is reasonable shape. It didn't crumble in my fingers. To give you an idea. The foam inside the door cards was in good shape. Only in bad thing on the car is the speakers. They rotted out. Which for its age isn't a big deal. I am leaning bad ground somewhere. When I started cleaning a few it would at least try to start for a second, better than acting like its flooded out. Tomorrow I will change the fuel filter and check voltages t the injectors. Once I check those that should tell me what's wrong.