NefMoto

I'm creating LPG optimized tune for my 2.7 '00 Allroad. I have weird ignition oscilations in my logs. There are no DTCs yet car is hard to start after prolonged time - it catches initially on cranking and then it feels like there is no power in combustion and have to help with starter to overcome additional 2-5 seconds. Could it be dying crankshaft or camshaft sensor?

(http://www.bildites.lv/images/bgyksvbz1ndufl5xx4b.png)

(http://www.bildites.lv/images/m9ibmlqurbpv20ajmz7.png)

(http://www.bildites.lv/images/xczk4dvwx94sui5bjhxg.png)

It's a torque intervention. Probably comes out because I always request lambda 1 and have advanced ignition. Will dig deeper and probably will deal with that ignition jumps.

I don't have a clue about coldstart issue yet.

Guys, please help. I tested everything I could imagine and finally flashed stock bin. Know what, erratic ignition angle is present still!  :o

(http://www.bildites.lv/images/skrzgfm0qt6arxkqk85g.png)

What direction should I look for?

How is the LPG controlled? Is there not some error with the injector control/slave computer etc?
How is the petrol behaviour? Any noticable differences on the stock file when you compare lpg to petrol?

LPG is slave controller. It takes petrol injector pulses, adjusts LPG injector pulse according to it and LPG pressure in line. When car runs on LPG, petrol injectors are disconnected and signal is sent to LPG injectors. It is so called 4th generation system by BRC. I haven't checked errors lately in VCDS yet I'm quite sure that this behaviour is from the begining of owning this car. There are no noticeable differences between both fuel types.

Can you spot something wrong in my attached log?

If you have any timing retard, then zwout will of course be a sawtooth since it is sampling per cylinder.
So if one cylinder has -4.5 retard and base timing is 9 degrees, you will have it jumping from 9 to 4.5 all the time and that is normal.

If you have no retard and this sawtooth - set KFDMDARO last column (50%+) to 50%+ threshold.
Might be anti-jerk routine going nuts.

Allready tried this and the result actually was no result - I still got zwsol pulling ignition angle.

As this is Allroad's ecu, ME7logger doesn't find all the variables I could log.

Is it normal that RPMs on full throttle sometimes jumps back or it is just logger issue? If this should not happen then I clearly have crankshaft speed sensor going bad.

(http://www.bildites.lv/images/56uvqkvv2601n0qympn8.png)

Sometimes. Thats why ECUxPlot has a filter for RPM...

That signal does not look right to me.

Also, set TMAR to FF and see what happens.

prj, You are golden! Das ist anti-ruckeln. Graph depicts everything you said including chainsaw ignition graph when knock retards are coming into effect. Is it G4 or G28 I should change?

3rd gear WOT pull:
(http://www.bildites.lv/images/405c5et3lwhrgkk9ffh4.png)

6th gear low RPM WOT pull:
(http://www.bildites.lv/images/yvrnjvxo39ii2eq03m.png)

ARMD will do all sorts of things if your RPM sensor is noisy.

I tested crankshaft (rpm) sensor with osciloscope. It looked good clean signal at sensor connector. Then decided to replace it anyway and found, that it previously had touched exhaust, got melted but fixed with wire isolation type.

(http://oi67.tinypic.com/35k1nid.jpg)

I replaced with brand new sensor unit. Unfortunately this wasn't the issue and I still have that ARMD timing pull on WOT at stock and modified bins.  :-[

did you try FF DMAR?

log B_ar?

Did you mean TMAR or DMARMX? There is no DMAR in my definition. Unfortunately ME7logger didn't find B_ar so I could not log it.

Answering regarding TMAR - yes, I FFed TMAR and there was no timing pull.

The wires are shielded. If the shield is damaged you will have noisy RPM.
Your RPM should NOT look like that. The problem is G28 signal.

The reason for erratic timing is the same G28 signal. Turning off ARMD will not solve the root cause.

Sender is now replaced with brand new yet I still have the issue. What more to suspect? Wiring loom or ECU itself?

Then your RPM signal is still noisy.

Is your RPM still erratic? If it is still erratic then make sure the wiring loom and especially the shielding is undamaged all the way to the ECU.
There can also be an issue with the distance of the sensor from the flywheel, the flywheel tooth shape and so on, but this is only relevant if you are using an aftermarket solution.