This is a continuation of posts I made on another thread:

https://www.northamericanmotoring.co...tart-help.html

The problem is with what appears to be a dead fuel pump on my wife's '03 R50. Basically, the first time the car stopped running, I determined there was no pressure in the fuel rail. Used my AutoEnginuity scanner: No fault codes and was able to initiate the fuel pump relay. System voltage was okay. Fuse was okay. There was fuel in the tank. Confirmed with continuity test that all wire in the harness plug to the pump were somehow connected to something, somewhere. Gas was in the tank. So, must be the pump?

Got a new VDO pump. Changed the pump and filter. Car got a little gas ignition, but not enough to run the engine. Then dead. Fuse was blown. Replaced the fuse. Car ran just fine for 17 miles. Then, no fuel pump noise with key in run position and no fuel rail pressure. Fuse and relay are good. Even swapped out several of each from other circuits and from my '03.

So, what better piece of test equipment for Mini parts than another Mini? Unhooked the harness from my fully functioning '03 and plugged it into the original pump. Small click in the motor, but it won't run. Same result when I plugged in the replacement VDO. Hooked harness back onto the resident '03 pump with no problems.

Now, one might think that the first pump died of natural causes and I had the bad luck of getting a dud replacement part. But, one more test. I hooked up the '05 pump directly to a 12 volt source and the motor runs (just for a second - don't want to burn the b***ch out). Hooked up the replacement pump. It too ran. Hooked them both back up to the '03 and '05. Pump motor makes one click but does not run, as above. Also, dismembered the first pump. No internal garbage. Will need a dremel to cut the case off the motor to do a complete necropsy, but I suspect it will just trash a motor for no good outcome.

I'm stymied. This makes absolutely NO SENSE to me. Besides now being a psycho OCD, I don't see a reasonable way out. I'm sure the dealer or a repair shop can get no further than I and would just keep throwing pumps at the car. I also don't want to buy a third pump if the replacement is good or if something peculiar is going on in the vehicle(s)'s electronics that's going to fizzle another pump.

Dear NAM colleagues, I turn to your collective intelligence and experience as the ultimate and final authority who can help solve this riddle. Please help. Otherwise I'll be in the nut house by this time tomorrow.

Thank you all.

 

Could something be clogging the fuel rail farther down the line that stops the flow? The car might sense the low fuel pressure somehow and cut power to the pump.

 

is it possible to swap out the ecu in the 2 cars to check that as well??

 

I've had one do the exact same thing, ended up having to drain the tank, replace the fuel filter, pump, and the rail w/ injectors because someone had sugared the gas tank.

 

Try physically measuring the rail pressure with a tester tool. Maybe the sensor the scan-gauge measures the rail pressure from is faulty. Don't trash a fuel pump if it works on a 12V power source. A pressure tester is about $25 from autozone, and it will help with your diag.

 

so what happened blue?