Engines not starting

[modifiede30]

I recently helped a friend transplant a motor into her BMW, and I'm having problems getting the car to start. Its turns over, but we're not getting any spark at the ignition coil, and the injectors are not firing. The engine transplant was from a 1988 eta to a 1982 eta (5 series). Harness, and all electronics were changed at the same time.

Tomorrow, I'll be testing the ecu and making sure that all the wiring is grounded and connected properly. The flywheel position and speed sensors are both fine, the knock sensor is okay, and the ingition coil itself is fine. Anyone have any other ideas on what I should check tomorrow aside from what's already mentioned?

[rs4pro3]

Let me know what you find as that is basiaclly the same thing My 86 528e is doing Like I said before I believe it might bt the ICM but have no idea.

[modifiede30]

Someone on a different board suggested the main relay. Now, I just need to find it. Do you know where its located on a 528e?

[rs4pro3]

Ya it is on the Engine side of the main fuse box. There two relays right infront of the plug for the computer. The front relay is the main and the back one is the Fuel pump relay.

[modifiede30]

What year 528 are you working on? Think it might be worth it to send one of your ecu's to me to test on mine. If it works, you'd know its not the ecu. Conversly, I don't have an extra to test with. Might help trouble shoot both cars. I'll send you mine if you want it. Maybe mine's not bad either and its something else. If it worked you could tell me how your car is wired, at least in a basic way.

[rs4pro3]

It's an 86 chassis I've got three e30's for it
one 027
one 007 and one rebuilt 027 by Programa
YA I'd be up to swapping ecu's
The newest O27 hasn't been run any and I believe the rebuilt 027 and 007 ecu's are fried as the car was run for a couple months with the High impedence 325i injectors in it.When the car was running it hesitated like crazy but had no vacume leaks A certified BMW mechanic who knows is stuff said Main relay, so we replaced it and it helped for a half hour then the car went back to it's old ways. But I believe the wrong injectors were the cuase of the Hesitation.
Last Thanksgiving we drove the car to knoxville, it ran great on the way p but lacked some power. Then while we where there We decided to check out a piece of land we have in the Smokies, in a developing subdivision. Half the roads are paved and on a gravel road the car bottomed out and drug bottom for a little bit. Then the car went to crap and died imediatly. it started back up but wouldn't go into gear at all. Finally after letting it sit for 4 mins it started back up and Slowly pulled it's weight the rest of the way. But then after stopping it took 10 min to get it to restart. So we made our way home but stopped for lunch and it took 15 min to start the car. then at ever traffic lite the cr had no power whats so ever. Some how we limped home. I ran a compression check and clyinder 6 was down 20psi. So I pulled the head and sure enough blown gasket. But when we bottomed out the Refence sensor pick up on the tranny got snapped off. So New used head and headgasket and new flywheel latter the car has no fuel and no spark at all. I can manual turn the pumps on but no start.

[modifiede30]

I just got a new ecu and relays. I'll throw them in and let you know what happens. I think the ecu's I have will be too old for your application. Also, I was told that the pins that go into the fuse box may be different than the original harness. This could create problems and the wiring may need to be re-mapped to make things consistent.

[rs4pro3]

All th pins appeared to line up fine. I'll check it with the old harness and see.

[modifiede30]

Its not the pins that are the problem, its the wires that feed them. They may not be the same wires that were in the other harness.

[modifiede30]

I finally got this thing running. Yeehaa. Sounds horrible, but it ran, and once about 2k rpm, it was very smooth. Maybe next week, I'll get it out if it clears up around here. I'd hate to get stuck somewhere in it, I'm not even sure the heat works yet.