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Discussion Starter #1
Hi.

I'm new to this forum, although I've been browsing for a couple of months.

I'm looking at buying an E28 M5 (SA spec), but the car that I've viewed has a starting problem.

The engines swings but does not start up, and when it does start up, it has a rough idle and then dies down again. I've been told that the fuel pump is at fault.

I've read up on the fuel pump problem, but is there anything else that could be a possible cause? I'm not much of a mechanic, and don't want to settle on a car that's going to cost me an arm and a leg to repair.

Any advice will be much appreciated.

Thanks

Ryan
 

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I would suggest bringing the car to a good mechanic that can diagnose the starting problem. You may get advice foom some of the experienced members of this board, however, they will need more information.

I bought my car for a resonable price with it running rough. The spark plug wires were crossed. Most solutions to problems after that were, unfourtunately, not quite that easy.
 

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potenially a alternator problem or maybe a starter problem. Both my brother and my uncle have owned E28 M5's and they have loved them. Easy to see out of fairly reliable, tight steering, decent on gas mileage. Good Luck!!
 

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Hi.

I'm new to this forum, although I've been browsing for a couple of months.

I'm looking at buying an E28 M5 (SA spec), but the car that I've viewed has a starting problem.

The engines swings but does not start up, and when it does start up, it has a rough idle and then dies down again. I've been told that the fuel pump is at fault.

I've read up on the fuel pump problem, but is there anything else that could be a possible cause? I'm not much of a mechanic, and don't want to settle on a car that's going to cost me an arm and a leg to repair.

Any advice will be much appreciated.

Thanks

Ryan
Remove a spark plug to check first if the engine is infact flooding itself.

If it is then you need to change the crank sensor at the front of the engine.
 

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As an additional precaution, before purchasing, do a full compression check on the engine.

But hopefully it is just the fuel pump or crank sensor, as already suggested.

Being an SA-M5 owner myself, I'd be interested in the details of this car.

Good luck on the diagnosis, and keep us updated.:M5thumbs:
 
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best thing to do is take the car to a good mechanic and have the problem properly checked out before buying the car. the set up on you car may be different than that of the U S an euro cars.
 

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Discussion Starter #8
Thanks for the input.

I'll get a mechanic to have a look at the crank sensor, fuel pump and also get the compression test done.

I've actually learnt quite a bit about the E28 from this forum.

BMWWGN, your thread is excellent, and will help me should I settle on this vehicle.

The VIN of this vehicle is DC98 2001072.

The car is neat, but there are a few items that need attention. So I'm still negotiating with the owner>

I will keep you guys posted>
 

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The VIN of this vehicle is DC98 2001072.
Thanks for sharing this.

According to RealOEM's database, the 535i bodyshell from which this car was built, left the BMW factory in May 1988, so it's a fairly late example - No. 59 of the 'official' 96 SA-built M5's, in fact.

Look forward to the updates.:M5thumbs:
 

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I hope this isn't too late....

Check the fuses first. E28 fuses are poor quality compared with the rest of the car. Fuses and contacts must be oxidation-free. Fuse conductors can crack (you may need a magnifying glass) causing high resistance.

It may be the fuel pump.....but I would expect a failing main pump to first give problems at higher rpm (4000-ish). Before throwing serious money at it, make sure the DME (main) and fuel pump relays are both good. A failing relay could give the symptoms you describe. It did with mine!

Note that the fuel pump relay is reliant on the DME relay.

On an E28 M5 these relays are mounted behind a vinyl cover above/in front of the glovebox, not under the bonnet with all the others. The cover is released by pressing the pins out of a couple of plastic rivets at the top edge (still available). Access is much better if you also push the pins out of the glovebox suspension straps to allow the lid to drop further: these pins can be re-used.

New relays are very cheap compared to one or both fuel pumps!

Then....check the vacuum hose to the fuel pressure regulator under the bonnet (the regulator is at the front of the fuel rail). Any holes splits or poor connections will cause problems.

Good luck.....do post an update!

Regards

Mfiver
 

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Discussion Starter #12
Thanks to everyone for their advise and input.

Just a quick update.

The owner says that he thinks it is the fuel pump, so he is repairing it before we continue with negotiations.

Hopefully this will resolve the issue, and prevent any uncertainties for me. He hopes to have it sorted before the end of the week.

I'll keep you guys updated.
 

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Discussion Starter #14
Hi Davidoli.

I had a chat with the guy last week. According to him, his mechanic has removed the fuel pump, and they are waiting for a replacement. I'm hoping they can get it sorted as soon as possible. It seems they had difficulties sourcing a replacement pump.
 

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fx

Have you bought the subject car yet?
 

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Discussion Starter #17
Hi BMWWGN

I unfortunately did not get the car. The seller could not resolve the starting issue, and sold the car as it was to someone else :mad:.

I was very upset as he did not give me the option to buy it (as is), knowing that I have been pestering him for the car for the past few months.

So, once again back to scouring the ads and the net, looking for a decent example.
 

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That's disappointing news - finding and procuring the car you want can be a frustrating process.
Good luck with your continued search.
 
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