S5 Turbo Fuel Issues

[Pete_89T2]

Originally Posted by JL1RX7

Even tried that. It still wouldn't start more than a second. It seems that it's not switching from start to run. Just changed plugs for shits and giggles. Still doing the same thing.

Yes on the switching relay under the steering wheel it has voltages where it should according to the FSM.

About to change the fuel filter today, again to eliminate any thing else.

^That's not where I said to measure it - you need to measure AT each FI connector to rule out a FUBAR'ed ECU harness wiring to the injectors. Which sucks because you have to pull the UIM to get in there, but that should be pretty easy for you by now.

A harness failure on a 25+ year old T2 isn't uncommon, and I have a hunch that the common +12V source to the injectors may be open somewhere - that would show up as a sudden no start/no run symptom. With the key in "run", you should be seeing +12V at the "A" terminal of all 4 injectors, and 0 at all the "B" terminals. Just use a paper clip to back-probe the connectors with your DVM, measure between each terminal and ground.