E30 starting probelm

[barrie325e]

Ok so i have an 87 325. The engine does crank and i do get power to engine but i am unsure what the problem is. I have changed out the spark plugs, and distributer, Could it be no power to the spark plugs? Or what else could it be. and how to get it running.

[Big Evil]

Engine must have 3 things, air, fuel and spark. When you did the plugs did you replace with oem? are you sure the wires are in the correct order? Try using an inline spark checker to verify spark. Is it getting (does it have?) fuel? Lastly what's the condition of the intake? Is the rubber sealed in between the MAF and throttle plate?

[barrie325e]

When cranking engine, there is no spark.

[Big Evil]

While cranking, does the check engine light on the dash go out? If not, it isn't getting a crank signal.

[tkeenan]

So then, if the light doesn't go out (far left check engine light) it would likely be the crank sensor, right?

I don't want to hijack this guy's thread, but I have the same issue after replacing a lot of things. (and the same car but off one year)
The crank sensor, however, checks out for proper voltage. The plugs have spark, the pressure regulator is new (the other one spit gas up through the vacuum), the air hoses are new and checked over, there is good voltage in the fuel injector sensors (and they are freshly cleaned) - yet it still cranks like this guy's car without ignition.
I also replaced the belts but that shouldn't be an issue as the cranking sounds really clean.

The fuel pump only activates when I hot-wire it, but even while hot-wiring it, I was unable to get the car to start.

I also, cannot activate codes by depressing the accelerator. Yet the throttle sensor still checks out with good voltage, which I intitally suspected in being the problem behind not getting codes.

Before I went about all this work, the car also started and ran, albeit really really rough.

To summarize:
1. cranks but won't start.
2. Fuel pump works but won't activate unless hot-wired.
3. Cannot pull codes.

Anybody have any suggestions before I turn this over to the shop?

[Big Evil]

If the check engine light does not go out while cranking then the ECU isn't getting the crank position and doesn't know when to fire the plugs. Sensor could be good but the wires are bad, wires could be good but the sensor is bad. Air gap between the sensor and pick up wheel could be wrong.

[tkeenan]

I changed out the cranksensor this week and still no change. The resistance on the new sensor equaled that of the old sensor, so I would assume that my no-start issue does not have to do with the cranksensor. Since the old one was frayed from getting caught in the pulley, I just left the new one on there anyway.

I went back over my timing belt job and confirmed that the cam and crank marks were still lining up.

The car actually started before all this work, but idled really rough (broken hoses, etc.)

Again, any idea why the fuel pump doesn't get electricity when I go to start? I know, or at least think the pump is good since I could jump it and it sounded like a normal fuel pump humming away. But then still, even when jumping the fuel pump, I can't get the car to start.

I also replaced the distributor and rotor just yesterday. I thought I had located my problem, because taking off the old one, I had found the rotor had bent some of the electrical nodes (the metal things on the outside perimeter) and left some gold metal shavings in the cap.
So after this, I could hear the sound of the plugs firing more distinctly, but with still left with a cranking and no starting engine.

[Big Evil]

Check the fuel pump, relay and fuse. Can you use a stethoscope and hear the injectors firing?

When you replaced the crank sensor you mentioned fraying? Are the wires back to the ECU in good condition/still attached? (could have gotten yanked out if it got sucked into a pulley)

And when you put the new sensor in, how close is it to the tone ring?