A couple weeks ago, my '04 R50 would crank, but not start. Had it towed to a shop specializing in BMWs, MINIs, and other imports. They got it to start, but ran a diagnostic scan anyway. No codes, so they suspected a bad fuel pump, since there's no code captured if the fuel pump gets power but there's no pressure at the rail.

I was able to drive the car around for about a week after that with no problems. Then it wouldn't start again. Fortunately, it was in my garage at home.

Today I did what I think is the right stuff to positively diagnose a dead fuel pump:

-Listen for pump when key is turned- no sound
-Check fuse- looks good
-Check relay- goes "click" when key is turned- good
-Borrow a fuel pressure test kit from parts store- no pressure on rail
-Remove back seat and check pump for power- Voltmeter shows 10V across some combinations of pins, starting when key is turned and ending after about 2 minutes

Is there anything else I need to try? I think it's time to order a fuel pump assembly, and I figure I might as well do the filter while I'm at it.

Any tips on doing this myself? Do I need to drain the tank? It got stuck in my garage right after I filled it up, so the tank is full. Will that be a problem?

Thanks for any pointers.

 

We have a fuel pump and filter replacement article on our site under MINI > tech info (tab at top) > fuel injection. It should help you while you tackle both the pump and filter. A suggestion for the filter, stick to Genuine. There have been more than a few complaints about the Vaico kit coming with o-rings that are too big, which cause a no start issue.

Filter http://www.pelicanparts.com/catalog/..._pg1.htm#item0
Pump http://www.pelicanparts.com/catalog/..._pg2.htm#item7

 

https://www.northamericanmotoring.co...placement.html

I would go ahead and replace it if I were you. It has one of the symptoms of a failing pump, sometimes works and sometimes doesn't.

It's going to be a problem having the tank full though. Gas is going to spill all over the inside of your car. Maybe someone will chime in with a suggestion on how to drain some gas out. Maybe google has some ideas. I guess if you trust your car enough, or have aaa, you could drive it until the gas is gone.

 

You can "wack" the pump....might get it unstuck....and drive it for a couple days...try to get it down to a half tank or less....or just sipion it off, and have lots of rags for the spillage.

 

I think the process of towing it to the shop was the "whack" that got it going again. When I whacked it today, I got nothing. So driving the fuel off isn't really an option.

Sounds like there's some kind of mesh in the filler line to prevent siphoning. So that's out, too.

Is there some way to drain it from under the car? Is there an easy-to-disconnect line down there? Even if I could just drain a few gallons into a catch pan and then pour them into a Jerry can... I just want to make sure I've got some overhead before I open the tank so I don't make a mess.

I ordered a new pump. Got a few days until it gets here, so I'm going to figure out how to drain some fuel while I wait.

 

I mostly agree about your diagnosis, but am a little concerned you are only seeing 10v and not more like 12.5V. The computer will not try to start when the battery voltage is very low.

Did you measure the battery voltage? Do you have an easy way to carry the battery to an auto parts shop for testing? I would if you can.

 

The pump and filter lift out from the top (there is a nice access hatch under the rear seat). If it isn't 100% full, then you don't need to drain it. I've read the suggest to tape a plastic sheet down around the area so drips don't soak into the carpet. Gas fumes are explosive. Read all the safety rules! Work outside and not inside your garage.

 

First thing to do is disconnect the battery. Second thing to do is make sure the battery is disconnected. Third thing to do is check to see that the battery is disconnected. Explosions are a terrible thing to witness, especially when you are very close to the action!

 

Battery voltage is a little over 12V. Should the pump be getting the same voltage? There are six pins going into the pump. I'm not sure what they're all for, but just noticed that some of them do get voltage when the key is turned on.

If the pump is supposed to get full battery voltage, but isn't, could that indicate a bad ground or a weak relay? Seems like 10V should still be enough to get the motor going, though...

Definitely going to disconnect the battery before opening the tank. And I'll push the car back into driveway.

The tank is about 99.9% full. I drove about 4 miles after filling it up. Maybe I'll try whacking the pump again now that I've got the back seat out. If I can get it started and drive it around town for an hour or so, maybe I won't have to figure out a way to drain some fuel.

And thanks for the tip about plastic sheeting. That's a good idea! I can use the same sheet when I do the fuel filter.

 

Siphon fuel from filler neck at gas cap into gasoline approved container(s). ( 7 gallons should be enough )
Put cap back on.
Remove battery from car, put up on work bench and charge battery out of car since you have probably by now weakened it.
Replace fuel pump making sure proper seals are in place and tight.
Reinstall battery after proper charge is complete.
Try starting again.

 

Does anybody know if the R50 has any kind of anti-siphon devices that would prevent a tube from reaching the tank through the filler neck? I've seen a thread about the second-gen MINIs having something that made it impossible to siphon through the filler.

 

http://www.gastapper.com/store/p3/Ga...Proof_Box.html

The manual version is about $40.00

 

By way of follow-up: the new fuel pump came today. By the time it arrived, I had already sucked 5 gallons of fuel out of the tank with a $12 manual pump I picked up at Home Depot. Worked great once I figured out how to wiggle the tube past some kind of anti-siphon valve or rollover valve about two feet down the filler neck.

I got the pump swapped out pretty quickly. Put everything back together, reconnected the battery, turned the key, and heard the wonderful sound of a fuel pump right behind me. I let it run for a couple seconds to pressurize the line, then cranked the engine and it started right up.

Drove around town for 20 minutes or so with the windows down to air out the cabin. The engine is running great!

Just wanted to share a success story. Thanks to everyone who provides so much excellent advice on this board. Happy motoring!

 

Awesome! Glad you got it running again

 

Great! Glad this fixed your issue and you can enjoy the MINI once again.