Urgent help needed, ignition

[SamE30e]

I need help bad.

I was at my friends house in guelph. About 75km away from my house. I had just washed my car earlier that day and it was running perfectly. I went inside my friends house for about an hour or two and came out and my car wouldn't start. It cranks over, but doesn't start, I cranked over for a good 5 minutes until I smelt fuel. I left it over night and came back in the morning and tried again, again, no dice.

I'm assuming its getting fuel because I can smell it.

There is no spark though, I pulled the wire off the coil and checked to see if it would arc on a ground (in this case the intake manifold) and again no dice.

From what I understand the coil is on a constant 12v and the ground is triggered by something. The coil is getting 12v, if I put a test light to the - side of the coil and the + of the battery and crank it over the light doesn't go. It has a brand new MSD Blaster SS II coil I put in 2 days ago with no problem and worked fine up until now.

I'm assuming that whatever triggers the coil is not working properly, all the fuses are fine and none are blown.

I'm waiting for the tow truck to come get it and bring it back to my house, I need my car urgently and if you guys could help out that'd be awesome..

Thanks

Sam

[jlevie]

The cause of a no spark condition will be one of:

1) Bad coil, ignition wires, rotor or distributor cap
2) No power to the DME ( bad mail relay or blown fuse)
3) No timing reference data to the DME (bad sensors)
4) Bad DME

In the case of 2-4 the injectors won't be firing and the fuel pump won't be running.

[SamE30e]

Whats the DME sorry i'm new to this haha. And is the relay under the dash or hood?

I know there is 2 sensors on the bottom side of the transmission. What does each of them do?

The Coil is new, I might try switching it back to see what happens.

If I put a test light to the positive of the battery, and the negative of the coil, should the light flicker when I crank it over?

[SamE30e]

I changed the coil back and nothing happened.

The fuel pump is working, I can hear it when I turn the key.

[jerods87e30]

DME = Digital Motor Electronics, basically your ECU

[SamE30e]

So ECU might be blown?

I'm going to change one of the Crank position sensors because it looks bum.

[SamE30e]

Is there any sensors or contact points in the distributor?

[jlevie]

Spark and injection on this engine is controlled solely by the DME based on inputs from the timing reference sensor mounted in the bell housing. The other sensor is the #1 cylinder ID signal and it is used for timed, rather than parallel, injection. The car will run with that sensor inop, but not if the timing reference sensor is dead.

The main relay is mounted on the three relay block near the left side fender well in engine bay. Normally the main relay is the one closest to the front of the car, but those relays could have been switched around in the past. To be sure that you are checking the main relay you have to match up the wire colors at the relay socket (see http://wedophones.com/BMWManualsLead.htm for wiring diagrams).

[SamE30e]

The main relay wouldn't be a problem because the car is turning on and off and the pump is working right?

When you say left side fender well you don't mean the power distribution do you? (With all the fuses)

Is there any other relays I should be concerned about? And you're saying that the timing reference sensor is the bottom one mounted on the bell housing?

Also another question, I welded a bracket to the body of the car under the hood, could that have done something to the car? I wouldn't think so seeing as how it drove perfectly fine afterwards, but just a thought.

My brother is trying to find a sensor sitting around at the shop to change and see if that works. If not then I'm guessing its the ECU.

[SamE30e]

Wait, if one of the 2 timing reference sensors didn't work, would there be spark or no?

[SamE30e]

So it's something in here. So far we know its not the coil, the plugs, or wires. It has nothing to do with the coil getting 12v because it is getting it. So its either the distributor, those sensors or the ecu.

Right?

[DaveSmed]

You got it. When screwing with those sensors, be careful not to switch the plugs around. They are interchangable, yet output a very different signal depending on where they are positioned.

Check and make sure the pin is still there on the flywheel. I would suspect the TDC sensor the strongest out of the two in your case, though it's a really tough call.

[SamE30e]

Pin is still on the flywheel, how do I check that? And where is the TDC sensor located?

Edit: Found the TDC sensor, by the diagnostic port.

I'm going to change the timing reference sensor once my brother gets home, if that doesn't do it then I'll check the TDC Sensor and the DME Relay ( I don't think that would be a problem because it fuel pump turns on when it's cranking.)

[delphini]

It seems your in a bind and the car is not at home so try this.....while cranking the ignition have your buddy try rapping (tapping) on the relays (located on the drivers side on the strut tower- there should be 3 in a row one white 2 orange IIRC) IF one of these is bad the car should "sputter" while tapping ("rapping").
OH SH!T is that a delphin "E" you got there ?? Yet another reason to get your baby on the road!!

[SamE30e]

The car is home now, its just freezing out. I'll try the relay thing. Thanks