Ok I really need some help. My 2000 audi s4 gave out on me. When it happened at first it would kind of start and die. So the motor would crank over rpm’s would go up to 1000 and then just die. Finally after a few minutes I got it to start and it actually got me home 25 to 30 miles away all highway. When I got home I waited a minute and tried to start it and the same thing turned over, started for just a second with no response to the throttle and would die. Spayed some starter fluid in the intake and it kicked over indicating a fuel problem. I changed out the fuel pressure regulator, the fuel filter and the fuel pump but the fuel pump that I ordered from highflow (really not happy with them fyi) did not fit in the basket the way the original pump did. Now even when removing the fuel lines from the fuel cap it does not pump fuel out of the output from the cap. Could this be something I messed up or because the pump doesn’t fit correctly? Also the pump is almost fully submerged in fuel and is definitely getting power. I can hear it powering on. I would appreciate any input more than I can ever express. Also I tested the old pump by connecting to the battery and it was dead. The new pump that doesn’t fit correctly does turn on when connected to the battery. I think that the fuel pump not fitting correctly is causing the problem but at this point I’ve already invested in fuel pump that didn’t fit right first, a fuel filter, and then a fuel pressure regulator and I don’t want to invest another $260 for another fuel pump if it’s not going to fix my issue. Fuses are also good. What in the world can it be? Shit if somebody gives me advice that works I’ll send you $40 that’s my word and I don’t break it
Have you contacted the supplier and told them the pump doesn’t fit? Take a photo of your new and old fuel pump and send it to them, It would not be the first time a supplier had a wrong part number in their system.
The only time I’ve heard of a submerged new fuel pump running but not pumping was because it was wired (and running) backwards.
If you can see power at the fuel pump connections and the pump runs when connected directly to the battery, polarity might be the issue. running the pump in reverse would just not work. Check that the positive terminal is actually connected to 12 v and ground to ground. It may be that simple.
If its wired correctly, there is a problem with current draw of the pump. If you can measure 12 V at the pump positive, there is a good ground and the pump won’t run, I’d start back-tracking the wiring to the relay. The relay may need to be replaced or the wiring may have been damaged.
So your saying that if I reverse the positive and negative wires in the clip that the pump will run in reverse?
Ok I am a man of my word. Mustangn and insightful send me where I can send your cash to and I will honor it. Gotta go get my refund from auto zone for the second pump I ordered tomorrow but you guys called and saved me $280 so I’m good with sending you 40 a piece as promised
Yes, it is a DC motor, the motor will TRY to run in reverse, IF the pump impeller allows. If not, it may just burn up the pump. Either way, if you hook it up in reverse, it will not pump fuel to the engine.