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1994 BMW 520 Auto - engine won't start properly

Hi Today after a about half a dozen short runs - it has been thrashed on those runs too - my BMW is now refusing to start properly.

It does crank, and can just about sustain itself at low revs (i.e. below the normal idle) for about 5 seconds before it starts to struggle further and then revs gradually drop until it stalls. Any pressure on the accelerator stalls the engine immediately.

I'm not sure whether it's relevant, but there has been an intermittent fuel smell from the car since I've had it (a few months). Economy has consistently left something to be desired. In the last few days however, economy seems to have hit rock bottom and there has been a persistent smell of fuel both inside the car while driving, and outside the car after parking up.

My guess is that it's something related to the fuel system, but can anyone confirm what the exact problem(s) could be?

Reply to
Ste
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Look for a potato that some kid has stuffed up the exhaust.

Reply to
R. Mark Clayton

Hi,

The Idle Control Valve(ICV) gets dirty and needs to be cleaned or replaced. Next in line is the Mass Air Flow meter(MAF). Then after that are the 02 sensors. And next is the ignition coils and their spark plug counterparts.

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for your parts- try to get OEM where possible.

So, those are the steps to fixing whats wrong, but it's just a guess. You need to get the error codes from the ECU read by a code reader. Either your BMW CCA club will have a reader you can borrow or a BMW independent mechanic can read it for you. Don't go to a BMW dealer for this. You are in a perfect position to get screwed with your issue. Best of Luck.

ER

Reply to
Enoch Root

Thanks for your suggestions. On further investigation, it seems there is no power to the fuel pump - either with the ignition turned on, or while actually cranking the engine.

sensors, and the spark plugs.

I'm also under the impression that fuel pumps are supposed to start up momentarily when you turn the ignition on (before cranking the engine), in expectation of starting the engine. As I say, there is no power whatsoever to the fuel pump under any circumstance, so do I also assume that the MAF is ruled out? If not, how might I go about establishing whether the MAF is working?

It also seems to me that the problem is more likely than not electrical. I've checked the relevant fuses. I'm also under the impression there are various relays that may need to be checked, but I'm unable to identify the relevant relays nor find information on how I might be able to check their functioning.

If you'd be able to help me any further on these questions I'd be very grateful.

Reply to
Ste

Fuel pump relay. Not sure where it is in a 520i right hand drive.

FloydR

Reply to
Floyd Rogers

As I said, I'm not aware of the location of the relay, nor how to test the relay if indeed I was able to find it. Surely someone here must know...

Reply to
Ste

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