duranvw

iTrader: (2)

Hey guys,

I've been working on getting my EVO IX running for a few months now. Basically what appears to happen is when starting the car it gets primed car starts for a few seconds and dies. No fuel pressure is established, it doesnt even sound like the pump is turning on at all. From what I've read in the forums the second fuel pump relay does not get grounded if the car possibly detects a problem thus not sending any power to the fuel pump for its own protection.

I do not throw any SES codes.

I have tried replacing the following parts;

1) MAF sensor
3) Fuel pump
2) IACV
3) ECU (another EVO IX stock one)
4) Areomotive adjustable FPR
5) Fuel pump relay #3 and resistor on the firewalll

What I did last night was run a direct 12V power to the stock fuel pump with a wiring kit and relay. (bypassing all the fuel pump relays that can possible turn it off and control voltage). The car will run however once it warms up to normal idle it goes insanely rich, past 11:1 AFR. During this entire time my fuel pressure gauge on the FPR is at 40-41psi (I know base should be 42.5).

So ultimately I don't think its the fuel system that is the problem but possibly another sensor that is causing the car to not turn on the pump for some other failure?

Does anyone know a list of scenarios that would cause the ECU to not power on the fuel pump?

I've heard possibly the crank position sensor which is going to be my next replacement if I can't come up with anything else. Not having thrown any SES codes is like working in the dark.

duranvw

iTrader: (2)

Nobody? I know I can't be the only one with this issue

jrblackSE

iTrader: (10)

Well sir since it runs you must have spark! There fore I would borrow a genesis or an OBD2 computer from mits and plug it in and let it run and watch all of your sensors with it! You should easily be able to monitor what is telling it to run rich and what is honestly not allowing it to start and run on the factory fuel relay. I purchased my car originally this way back in 08 and after replacing all of the cam sensors and fixing a few voltage shorts it actually ended up being the crank sensor. Apparently, when you have a faulty crank sensor it allows it to turn over and maybe back fire once in a while but it will not allow it to start. If you are able to get your hands on a computer to monitor your car, watch what the crank sensor does and make sure it is showing rpm and I believe that means it is good and reading properly. Best of Luck I hope I am some help to you.

duranvw

iTrader: (2)

Well I replaced the crank sensor, still having the same problem.

The car will start, the fuel pump gets 12V for about 5 seconds, the power is shutoff at the fuel pump and car dies. I have spliced open the power and ground at the fuel pump harness to test the power. The car will start again no problem but die the same way every time.

I suspect it has to do with the fail safe fuel pump relay responcible for shutting down power if something isnt operating correctly. I swapped relays that isnt the issue. Also replaced the above items.

I havent tried TPS, could this possibly cause an issue like this? Again I throw no codes so it's a little difficult to troubleshoot.

Topher86

what source is the 12v?

duranvw

iTrader: (2)

When I'm reading the 12V it's off the power wire to the fuel pump assembly just inside the hatch under the back seat. That power is cut off but the ECU and fuel pump relay I assume, just don't know why it's happening