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Discussion Starter · #1 ·
I have what I think is a bad siphon pump, or at least a bad connection from it.

I had the large rubber seal on the right side access port replaced a while ago due to leakage when the tank was full. After replacing the seal, there was no more fuel leak (good!) but I started having problems running out of gas with the guage at about 1/4 (bad!). Running a bunch of experiments with the OBC display test for tank levels, it looks like I consistently starve for fuel with about 12-14 liters of fuel remaining in the left side and nothing on the right. Also, as the fuel level goes down, I don't see the left side siphon to zero with some quantity on the right. I see the left stay about 12-14 liters (plus or minus depending on car movement) while the right side goes to zero.

Nothing was touched in my left side tank, so I suspect the siphon pump wasn't hooked up correctly when they reassembled the right side pump/sender assembly after disconnecting all the hoses to replace the large port seal.

Do y'all agree or not?

Luckily, the work is still under warranty, so I have an appointment next week to have it looked at.

Thanks!
 

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Definitely agree with your diagnosis. They failed to make the proper connection back into the
siphon transfer system when reinstalling the pump assy.

Regards,
Alan
 

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Discussion Starter · #3 ·
Update on my siphon pump woes.

I had the shop look at it and it was definitely a problem with the connections to the siphon pump. The tech said that when we went to pull the main pump up to look at it, it felt like one of the clips that holds it into the receiver wasn't engaged. This caused the connection to the siphon pump to not be made, causing the problem. The reseated the main pump after checking the o-ring on the siphon pump connection and now it looks good. With about 24 liters in the tank on the way to drop the car off, the dash readout read 12/12/24L, but on the way home it read 0/24/24 like it should.

BTW, the shop was Dinan in Campbell, CA (where I've been taking my BMW's over 15 years) and they didn't bat an eyelash about honoring their 2 year warranty on all service, so it didn't cost me anything to fix it except time. Now I can feel comfortable about using the entire fuel tank capacity instead of having to fill up before the readout got down to 75 miles.
 

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Dinan: My only shop also

Excellent! Glad you got it taken care of.

Dinan in Campbell is the only shop that touches my car when I need something requiring a GT1 or other
specialized tooling. They are also a great source for miscellaneous hardware, etc..

All of the tech's there are superb, but I always specify Matt Jordan. Matt has enormous experience and
skills, plus he's a great guy. In the event you don't have a personal "one-on-one" history or preference
when you take your beast in, request Matt to work on it. He really knows how to dial-in the alignment
to give you the handling characteristics you want. Be sure to have him show you his E34 M5 that he has
been restoring. It has a paint job that is incredible.

He had it done at Dell Auto Body, which is just next door. They do the highest quality work I have ever
seen. If you ever need some repair be sure to go over there and check them out. The are the factory
repair center for Bentley and Aston-Martin. Ask Carlos (manager) to give you a tour. They did some
insurance repair on one of our vehicles and their work was flawless.

Regards,
Alan
 
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