help no buzzing

Hi,

Sorry for my lack of input on the forum for ages,I really need your help now.I wanted to run my engine on my m3 today as its kept in a carcoon and i'll only deflate it and play with the car in good weather which is not very often in this country.I took the battery conditioner off put the key in the ignition turned to the first click dipped the clutch all dash lights on and correct turned over nice and quick but didn't start first click .I sat there and thought it over no fuel pump buzz.Please correct me if I am wrong but I should here the pumps pressurising I did give the relays a little tap behind the header tank with the ignition on and heard no clicks or pops.I think my alarm has caused this problem as I ran the car a while ago and put it away alarmed it and now it won't start.

Many thanks in advance,,Gaz   

sporty,,

Thanks for your helpful advise as usual,I got home today at 2.PM after the morning shift at airbus deflated the carcoon and started work on the car.I rang Geoff at eta who pointed me in a couple of directions with what might be wrong,,I removed the back seat got the float and pump out connected the pump cranked the car over the fuel pump motor turning doh!!! refitted it all no problem.Car still not starting before that removed no4 plug dry no fuel on them,,looked behind the header tank removed the silver relay wiggled it about, still no starting took it totally out I'm getting two lives into the relay holder so alarm is not switching the pump off? The silver relay sounds worn inside as I rattle it around next to my ear so I'll try one of them from the stealer's tomorrow.I think the relay is the DME one which is a regular one for the Porsche gang to have a problem with am I barking up the right tree?

Regards Gaz,,,also many thanks ETA BMW.

Hi,

I put the part number of the relay into google and loads of info about none starting BMW'S of all different series came up.I ordered a dme and fuel pump relay today from C3,I will get the parts by the weekend so I'll let you know if she starts then.I am a bugger for messing with things so I took the relay (silver one behind the header tank)apart two resistors and a copper coil inside and a large corrosion blob on the coil its got to be my problem.

regards gaz,, 

screamingflat6 wrote: Hi, Still not starting! I bought the fuel pump and dme relays which I installed and still not firing-up? The battery was cranking the car over ok but it was *uck*d really quick,tried another battery from another car of mine and the same.I ran the car a while ago on the spot in the carcoon,It was running great I let the fans come on turned off  the engine and attached the trickle charger zipped the car up into the carcoon and thought to myself I will run her up again in three months,.doh not bloody starting.I have other cars which I store and none of them have failed to start yet.I have now rang the alarm fitter and he's coming tomorrow I hope he can sort this out for me tomorrow as I just don't hear the injection making a buzz click or anything I'm sure that I should here the pump buzz for a couple of seconds on initial start up. Regards Gaz

Gaz, IIRC, they do not 'buzz', as the fuel pumps only go live on cranking the engine.

I'm late to this so you might have looked at these already but it could be one, or both, of the two crank sensors.

Hope you have a working car again very soon.

Cheers

So:

When you have checked that you have good spark from the coil HT then check that you have a good spark at the plug (ie after the disi)

Next, ensure you are happy that you have got fuel to the fuel rail. You have disconnected the return line before the FPR if you connect a fuel hose to that you can collect the fuel in a measured jar and calcualte the flow rate. - There is a spec value that ensures that the flow rate is sufficient, but this is probably not necessary to get it going. (note - you can create a couple of jumpers that replace the main and fuel relays to activate the fuel pump without having to be turning the engine on the starter)

Have you tested that the injectors are injecting? Turn it over with the spark plugs out and you should get a good indication - smell of fuel and a puff of atomised fuel from the plug holes - all four.

If not, it is probably either the engine position sensors or the ECU.

The 2 position sensors are down below the starter motor but in line with the flywheel. They plug into the engine loom behind the airbox (under the wiring cover). The two sensors are both the same part but you need to ensure that the right sensor is plugged into the right connector. ie do not mix them up.

There is a third sensor higher up - There is no need to worry about that. It is for diagnostics only.

There are known problems with ECU that are notoriously difficult to find. There is a school of thought that says if you give the ECU a gentle tap or two from below and/or dissconnect/reconnect and waggle the connector you may make some progress. Also try turning it over while applying moderate upward pressure to the ECU connector. This worked for me when all else failed. Then I had to fix the ECU!!!

screamingflat6 wrote: 10,If I have a spark and fuel whats next on the check list

If you have a spark (at the right time) and fuel it should at least make an attempt to start.

What next, depends on your tenacity, and determination to fix it yourself. There comes a point when you pay someone else to fix it for you.

I hope that your next set of tests finds the solution. 

Hi and thanks to you all for your help,

As Victor meldrew would say "I just don't bloody believe it!" I have fixed the car and its a really daft thing that my 67year old dad said have a look at.The rotor arm!!!!  it visually looked like new but I did as Dad said cleaned the copper band on fwd part of the rotor also cleaned the cap terminals and wire brushed the plugs that had been removed yesterday so the head was free to evaporate any fuel in there.I reassembled the car and Bang! first turn of the key she ran sweet as a nut,I then let her run until the fans came on. 

PS, will start her more regularly now .