checked the thermo sensor its good
original hub and timing marks
ordered a fuel pressure gauge to see if pressure is correct
thermowax is original and throttle cable has been checked
giving it throttle does nothing when trying to start it after it dies

 

If the car dies while idling is the hood opened or not. Also, you might want to play w/the throttle stop screw to increase the gap a bit w/respect to how much it is opened as previously suggested and see if this changes things for the better, but make sure you reference how much you turn the screw in case you want to return it to its previous setting.

 

so hooked up an inline fuel pressure gauge and it's reading 28-30 psi at idle. Surprisingly it wouldn't die this time so I had my brother shut it off. Pressure dropped to 22 psi and when trying to restart it dropped all the way to 0 psi. My best guess is fuel pump(again), or maybe the relay?

 

Hood is open. tried adjusting the throttle and it didn't help

 

just tried testing the pump from the short circuit and nothing. I can hear the relay clicking on but no pressure

 

You mean you jumpered the fuel check connector and w/key to on there was no pressure? On an S4 NA, the circuit opening relay, located under the dash and just to the right of the steering column, has a Blue wire (top row far right position) that should have voltage w/key to on and the fuel check connector jumpered. You could also jumper the bottom two wires of the relay which accomplishes the same thing as jumping the fuel check connector.

 

yep thats what I did. Car is back in the shop since the pump is under warranty

 

The pump just receives a signal from the relay so either the relay is doing its job or it is not. If not, then the pump is not at fault.

 

Ok so first off sorry for the late response but life happened, anyways got the car back with another new pump and it ran fine for about 3 weeks and now it's acting like it did the first time the pump went out, i.e. lack of power, backfiring, sputtering etc. Changed the plugs which were carbon fouled, still running like crap so I did another compression test and it's showing 122 on the front, 125 on the rear. So compression is still Damn near perfect. Now I'm thinking the pump is failing again. What would cause 3 pumps to fail in under a year?

 

I've heard that a pump can die if starved for fuel. Did you replace the fuel sock in the fuel tank or reuse the old one? But this does not explain the fouled plugs, though.

 

As far as I know the sock was replaced, as I said it was done by a shop. Think I'm just gonna wire in a walboro of its the pump again.

 

I believe those are for a turbo.

 

Yeah I know lol, was being optimistic about swapping my engine. If only it was that easy. Anyways I've got a couple videos of the car running and the fuel pressure still looks good so im at a loss at this point on what to look for.https://youtu.be/Wk7iC-FxaGQ
https://youtu.be/ck1hLcdJ9dQ