5000turboman00

how can I make sure my fuel pump check valve is working properly. Im tryin to figure out a hard start problem and im thinking this may be the problem. If i put a fuse in fuel pump relay and get it going for about 10 seconds, should the car fire right up...and what would this tell me? Also when changing the fuel filter, if there is a good amount of gas coming out what would this hint about the check valve?

boxerfan

running the FP for 10s should pressurize the system adequately. then see what pressure you have at the filter. Run again for 10s and let the car sit for 4 hours and see if there is still the same pressure as before.

If the check valve is the problem then the 10s run should allow the car to start right up because the fuel pressure will be adequate. The CIS fuel distributor function on pressure differential. If the pressure is inadequate you will have poor/no fuel delivery.

You also might want to check the fuel pressure accumulator at the rear subframe. Sometimes they can leak and release the pressure as well. HTH.