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Ignition timing / ignition idle control


Spreast

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Hi Everyone.

I am experiencing some trouble with my ignition setup on my M50B29 Vanos engine with Link G4 with V4.10.2 firmware from 2014.

Background:
The car was initially built in 2011 with a M50B28 non vanos engine with pretty sporty cat cams and have been working fine until I totally rebuilt the engine to a hybrid M50B29 with a vanos unit mounted on an non vanos head to get 7mm valve shafts. head also have dual intake cams from M54 and M50, M54 on intake and M50 on exhaust. This to make the engine a little more calm on low revs. I experienced some troubles with the previous setup with the cat cams on low revs and was struggling with a calm idle. We solved that with ignition idle control. This setup worked like a charm with the old setup and i had no problems with emission tests on our yearly vehicle controls in Sweden. Engine has a Innovative LC1 for lambda adjustments. This is when i noticed there is something wrong with the ignition. Changed all the ignition parts, trigger sensor with new wiring, new plugs (NGK BPR7ES), new NGK Coils and wiring to the ECU, checked the ignition timing again, measured the cam positions.

Problem:
Engine is starting and running fine, ignition timing is strobed and zeroed with the ignition idle control disabled. But still when i was driving the car I noticed it was running warmer than usual. I managed to get the car trough the emission test with ignition set to 3 degrees and later on noticed that the idle ignition control function was active again even so i disabled it. So I have strobed the ignition, disabled the idle control and still it re-activates and causing problems and the TDC seams to have a life of it´s own changing around. Since this problems accrued the vanos is not activated.

Engine Specs:
M50 cast block, M50 non vanos head with vanos unit mounted
Forged rods and pistons
M54 intake cam on intake, M50 intake cam on exhaust.
Standard intake
2200cc injectors with nuke rail and fuel pressure regulator
Custom exhaust manifold with a Borg Warner S369SX-E

Someone have any ideas or have faced the same problems? All suggestions are welcome!
if there is any further information you need please don´t hesitate to ask!

Best Regards, Fredrik Östman

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Can you attach the tune and a short PC log of it running preferably when it is exhibiting the problem.

Im not sure if the M50 is susceptible, but I remember in the early 90's some BMW's that I played with the rubber inside the crank pulley would come loose and the pulley would slip around, if you didnt notice the timing would be miles off and would appear to keep changing.

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2 hours ago, Adamw said:

Can you attach the tune and a short PC log of it running preferably when it is exhibiting the problem.

Im not sure if the M50 is susceptible, but I remember in the early 90's some BMW's that I played with the rubber inside the crank pulley would come loose and the pulley would slip around, if you didnt notice the timing would be miles off and would appear to keep changing.

Are you talking about the harmonic damper? If so i had it checked when i was assembling the engine and it was fine, its a 2.8L damper from the M52B28, I think you are referring to the M20, they had really weak dampers and I have experienced the issue myself

I might have a log file but if not ill try to do some logging to see if the problem occur again.

Best Regards.

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On 7/14/2020 at 11:54 PM, Adamw said:

Can you attach the tune and a short PC log of it running preferably when it is exhibiting the problem.

Im not sure if the M50 is susceptible, but I remember in the early 90's some BMW's that I played with the rubber inside the crank pulley would come loose and the pulley would slip around, if you didnt notice the timing would be miles off and would appear to keep changing.

Here is a logfile when we adjused TDC, Ignition Idle contol is disabled and lambda sensor is freshly calibrated and tested.

Any ideas why the idle is jumping on AFR 14,80? gets stable when i add more fuel, trottle body wrongly adjusted?

Had to compress the log file as it was 25mb

 

Best regards, Fredrik

 

TDC Config-Log 20-07-20 9;27;06 pm.rar

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