Turns over but doesn't start.

[Macv]

So this weekend I took off the engine cover (94 540i m60) to clean. The only thing I touched was the cable that goes through the cover. Of course I had to move it to take the cover off. Other than that, that's all I touched.

This morning I go to start the car and it won't run. When I put the key in, it makes a small buzzing sound and I don't hear the usual "running water" sound (injecting gas I expect). When I turn the key, it turns over but does not start.

I don't know how to check to make sure the sparkplugs are working and I think it's just not getting the fuel to start.

What should I check and how do I get it to start?

[Macv]

Ok, So I checked the fuel lines, and every plug I thought could be disconnected. I pressed the gas a few times, and just let it sit with the key in. About 2 minutes later it just starts right up.

I'm happy it worked but I really need someone to tell me how to prevent this. If anyone knows what has happened please let me know. I'd rather not go through this again. It hurt me that she didn't run. :)

[Macv]

Part 3.

I had put the cover back on when I started it the first time. It did not work at first. After I took the cover off for a bit it worked, like I said in my other post. It ran real good for about 5 minutes. Well since it was working I put the cover back on. I started it with the cover on and it worked ... for a minute then it completely died.

I feel as if there's something to do with a vacuum or something to that effect.

Please please please someone give me some insight.

[31Hertz]

Part 3.

I had put the cover back on when I started it the first time. It did not work at first. After I took the cover off for a bit it worked, like I said in my other post. It ran real good for about 5 minutes. Well since it was working I put the cover back on. I started it with the cover on and it worked ... for a minute then it completely died.

I feel as if there's something to do with a vacuum or something to that effect.

Please please please someone give me some insight.

It sounds to me like you might be disturbing a loose electrical connection. There is quite a bit of wiring under there. Check all of your connectors for tight fit. Any wire that is underneath the cover could be suspect (trace 'em to the connector). I think (could be wrong) maybe the wire for the Crank Position Sensor runs through there too. That will definitely cause a "no start" if not properly connected. Maybe someone else has 'nuther idea?

[Macv]

I've checked the crankshaft position sensor and it looks good. To my knowledge, the car wouldn't have started without the crankshaft sensor working. Maybe it cut out, I dont know. But I CAN get my car started, for about 5 minutes anyways, and ONLY when she's cooled down.

[eduard]

Check timing sensor I had the same problem with my car. M50 engine.

[31Hertz]

I've checked the crankshaft position sensor and it looks good. To my knowledge, the car wouldn't have started without the crankshaft sensor working. Maybe it cut out, I dont know. But I CAN get my car started, for about 5 minutes anyways, and ONLY when she's cooled down.

There are lots o' connectors around that area. Check 'em all; especially the large bundle... Check for sharp bends or abrasions in the wiring where the conductor could be damaged or exposed. It sounds like wiring because of contraction and expansion between cooling and warming can cause connection and disconnection respectively. It could be a bad crimp within a connector... Anybody have other ideas?

[Macv]

I had talked to my local bimmer tech and he said basically the same thing. He mentioned all the physics of heat expansion and contraction.

How can I test these wires?

[MBXB]

The small buzzing sound is your Idle Control Valve. That's normal.
Get a can of Radio Shack Electronic Cleaner/Lubricant and spray it into each connector before you disconnect. It should make removal easier. Then respray into each side before reconnecting.

Check the Throttle Position Sensor connection (on the throttle body) and the Cold Air Temp Sensor right next to it (goes into the right front of the intake manifold)

[BillionPa]

i think you are in line for a new fuel pump. they die on M60s.

try replacing the fuel pump relay first though.

and if you do need a new fuel pump, buy some FP60 and run it in every tank, it makes the pump last longer, and you get better gas mileage.

[Javier]

They do tricky things wile going out. You should learn how to bypass the fuel pump relay and do it wile refusing to start. If you don´t get the hissing associated to fuel running trough the injector rail and FPR, pump is dead (unless fuel pump fuse is dirty, corroded or broken).

Javier

[Macv]

Anybody have any detailed descriptions on how to do this? I've never messed with fuel things on cars :( one of my weaknesses. Can the Bently walk me through this? I can understand the logical things like, bypassing and such ... but don't know what is where and likewise.

[shogun]

This is the starter relay, just as example how to bridge your fuel pump relay. The starter relay is bridged pin 30 to 87.
You can see the tongues under the fuel pump relay, so you can see where to bridge
http://www.nmia.com/~dgnrg/jumper.jpg

[Javier]

also the picture will guide you to the fuel pump relay, just pull it out to identify the 30 and 87 poles.

Jumping (http://www.bimmer.info/forum/showthread.php?p=124782#poststop) pump relay.

Javier

[Macv]

Just a recap: ... or ending:

I had checked the fuel pump and such and everything looked fine. I wound up taking it (towing it) to my local tech so he could check the crankshaft sensor for me (don't have an ohmeter). And what luck, thats all it was. Thank you all for the help!