e30 m42

[blueapplesoda]

Problem is the car is firing on only 2 cylinders.

I'm testing an ms3 + ms3x, wired in to a factory 88-pin DME connector for an m42. I'm using the ms3x logic ign outputs (A-D) through 120 ohm resistors to trigger 4x bip373's, output through the factory 88-pin DME connector to the coils. I didn't have access to a timing light when I tested the ms3 on my buddies car, as the test vehicle is a little hard to come by. I have to arrange for one of my friends to bring his car by from a good distance away.

I confirmed that the BIPs were wired correctly, and tested the BIPs with an LED tester while on a stim. I used an ohmmeter and tested the harness to the coils and made sure my diagrams were correct and I wired the adapter correctly. Injection is done via 3.57 mainboard outputs, to the adapter. I've triple checked the connections, everything seems to be where it should be, physically.

I was also wondering if anyone has any information on the tooth #1 angle for the m42. I haven't manually counted the teeth or anything, but I'm certain it is a 60-2 wheel, and online sources say 118 degrees for tooth 1 angle. Angle might be slightly off, but should not affect the operation to this extent. Composite logger shows clean and solid Crank signal, and cam signal is clean, but only comes in when the engine is above 1100rpm. Car rev's smoothly (however smoothly a 4 banger can rev on 2 cylinders) and there is no real sync loss during operation.

m42 coil packs are sequential coils, confirmed with diagrams and Matt at DIY.

Apologies in advance for the clusterfuck of ideas and thoughts, I've been pulling my hair out over this box.

MSQ and datalogs are attached with the last bit of settings I was dicking around with if anyone wants to look it over.

Picture of the setup I put together..



Derek
DedericMS

[justnsk]

I think when you use 4 ignition outputs for running wasted spark at 4 cyl engine, you should set "wasted COP" in ignition options. In your current Msq only 2 outputs are enabled because you have "wasted spark" setting there.

[blueapplesoda]

Well that's embarrassing. I completely looked over that in my frustration. Thanks for catching it, I'll give that a shot.

Derek
DedericMS

[blueapplesoda]

I changed the settings to wasted COP, single wheel. I set the timing to fixed timing of 15 degrees with a crank timing of 10. We start the car and it still sounds like a subaru. I get a timing light from a friend, but we couldn't find the TDC mark. I made sure all four coils were firing with the timing light, even though we couldn't find out when they were firing. I cleaned up the toothed wheel and found the TDC mark. I manually counted the teeth passing the sensor clockwise, and its either 20 or 21 actual teeth (starting from the first tooth after the missing teeth) till the motor is at TDC. The TDC pointer is not very clear where it is pointing, as it was about an inch away from the tooth wheel, so the tooth count is a close estimate. That should give me a tooth 1 crank angle of 120 degrees if its 21 teeth, or 114 degrees if its 20 teeth, correct? I changed the tooth 1 setting to 120 degrees. I wasn't able to start the car after that, it cranked over a few times then stopped dead in its tracks like the timing was way off during cranking.

Any ideas are appreciated. I'm building this for a customer in Australia, so I want to make sure everything runs right before sending it across the world.

Derek

[LoukakIS]

hi, I have an E36 m42 and the first tooth angle is 118, messured with a timing light. I assume you should have the same. If you have sync loss, try first to unplug the cam sensor.