[Bmwe21m50turbo]

Hi all,

Ive got a weird problem with my ua4c that ive been chasing for several months so i hope you guys can help me out a little.
Car is a bmw e23 with a m30b32 turbo engine. I have driven this car a few years ago with my ua4c but ive changed some things in my setup (other cylinder head, head gasket, exhaust manifold and wiring loom). The car uses wasted spark/ignition.

In the past i had some rpm cutting problems with my VR sensor so i swapped it for a hall sensor and im using a 60-2 and that seems to work fine now.

so the problems began when i tried to adjust my trigger angle. Ive got the feeling its drifting. I can put a trigger angle in and the car runs fine, then i do a short pull and the car gets les power and the turbo is turning faster afer the pull. Almost like the ignition timing gets retarded. if i add some tirgger angle it works fine again until i do a pull then the power goes away and turbo spins faster. Sometimes the car dies and wont start, i have to add 20 or 30 degrees of trigger angle and it starts up fine and it all happens over again.

i tried to adjust the trigger angle with a timing lamp but it doesnt even run when the marks are lining up on the harmonic balancer and engine.

Ive tried changing firmwire laptop tunes and wiring and im suspecting a software/firmwire issue. But so far still no solution. A nearby friendly tuner took a look at it and is stumped aswell.

As i said first time i used this ecu (about 4 years ago) everything was fine.

My trigger signal looks good, using falling edge, i however did remove a capacitor (c24?) from the board when i tried to fix my VR signal.

For now im kinda at the point of pulling my hairs, im tinking about buying an EMU classic but thats not a real solution for the problem. Maybe i should make a datalog but i havent had the time for that yet.

I hope some more knowledgeable people here can point me in the right direction.

thanks alot for answering and taking the time to fix this problem.

[PSIG]

That has to be frustrating! Find time to do a log or two of the issue, and post the exact tune used to take the log.

I presume you "burned" any new settings? When loading firmware or tunes, did you run EEPROM_Clear on the Mega before loading? Have you tried a new TS project? Are you sure you are timing #1 cylinder to the timing marks with Trigger Angle? Are they the correct timing marks? The timing not lining-up is a large concern. I'm looking for a simple issue.

I have not seen this exact problem before, except when the trigger wheel was mounted to a damaged balancer (the outer part slowly moved from the inner part). This should not be a problem if your wheel is stock, but I would check everything for something you don't expect.

[Bmwe21m50turbo]

well i made some datalogs but the forum wont let me post them they are too big.
You need the composite logs right?

i burned any news settings but i also used to do that with a running engine, i believe thats not the best thing to do and may cause corrupt data?

we did an eeprom clear on the mega and tried different TS projects. Im sure its cylinder one and the timing marks are orignial. I ruled a faulty balancer out i was convinced this was the problem but it seems fine after getting it off.

[Bmwe21m50turbo]

well i compressed the log with winzip i hope it works!

halfway through the datalog the power dissapeared again and i put 30 degrees more trigger angle in and it went better.

[PSIG]

Your tooth log looks good. Use the ZIP file to collect your tune file, and your run logs. Always together.

Start_log_file.jpg (19.68 KiB) Viewed 392 times

[Bmwe21m50turbo]

ah yes i see here we go again.

Btw i had to keep adding trigger angle to keep it going.

[jonbill]

how much trigger angle are you adding? can you identify when in the log the trigger angle was incremented?
Have you got any pics of your trigger wheel arrangement? is the trigger wheel bonded on to a pulley?
is the pulley keyed on to the crankshaft? have you had pulley off since it last ran well?

[Bmwe21m50turbo]

In the log i started at about 90 degree and eventually ended up near 130. It is a keyed harmonic balancer and i made a few stripes on the crank and pulley to check and they stay at the same spot.

I will try to identify when i add trigger angle in the tune, mostly after it got some boost and the power sapped away. I slow down and let it idle (sometimes with throttle because it wants to die) untill the rpms rise a little bit because i adjusted the trigger angle.

The tooted gear was a press fit around the harmonic balancer and to be sure i made a few spot weld around it aswell. This is the only photo i have right now.

One thing may be wrong about my setup, i put the 2 missing tooth just after TDC. the sensor is located about 44 degrees before TDC.

[jonbill]

Are you always just adding trigger angle? do you ever take it away again?
Please share your tune. (.msq file).

[Bmwe21m50turbo]

well it depends sometimes i just try a number to see if it fires up, if i decrease the trigger angle it dies eventually unless i subtract enough (but with engine off because it will die when i do it with running engine).

btw i know my tune is bad but it needs to be stable to tune it ofcourse.