Well I had the mechanic change the spring in my s-fmu and no change in fuel pessure. He rechecked all the fuel lines and they are where they are supposed to be. He checked the fuel filter and it is not clogged. I called Hahn yesterday and the tech guy said that it sounds like the pump may be running backwards. This makes no sense, it all worked fine for almost a year untill I blew my motor and had it rebuilt. The pump is stilling making noise so it is working, but it is only making 20psi of fuel. Does anyone have any clue as to what is going on? Please I am in serrious need of a car, and I want it back to go to hot impor nights in Texas next month.
Anything will help,
Patrick

Is the pressure dropping off right after you turn the car off or turn the switch to activate the relay, then off again? It should wait at least 2 min before it drops if it does, then there could be a list of things. Common ones are leaky or stuck injector, leaking fuel feed or return line, bad regulator (your case, most likely not), bad check valve in the fuel pump (stock unit). Check the voltage going to both pumps. You can eliminate the regulator by crimping the return line right before it and see if it bleeds off still, then the regulator is out of the picture and work your way from there.


Hope this helps

did he touch any of the fuel lines for the pump? maybe he put it on backwards if so...also is the fuse under the hood still good? relay? maybe he does not know how to adjust the fuel pressure... since u know your car go over there and look at it, i bet you can figure out whats up...



Michael 99gs
HRC Stage 2
http://www.dreamwater.net/purplebeast

Ok, this may sound dumb, but is he adjusting the idle/static fuel pressures by turning that adjustment screw on top of the regulator? My screw is almost all the way in to get 50 psi of fuel at idle..be sure the bottom fuel hose on the FPR is going back to the tank, and the side post is going to the fuel rail..I have the 2.72" disk and short, dark spring in side of it..

Thanks for the feed back. I don't think he touched any of the fuel lines at the pump because it was already installed before it got to him. I'll ask him about how quickly the fuel press. drops when the car turns off. I'll also tell him that he may need to adjust the static screw down further. I can't get to the shop because he is more than an hour away and now I have no car. Told him about pinching the fuel return line and he said that he would try it. I'll have him check the fuse for the pump, but if the fuse was bad wouldn't the pump just not even come on. This sucks tomarrow I am going to call arround to see if there is a shop in the city that might be able to gifure it out. I appriciate all the help guys.
Patrick