Vibration! A cure for bad vibrations, Spark Plug Caps!!

[labanina]

Should i try increasing CO for cylinders 2 and 3? Or reduce 1 and 4?

Lean mixture burns hotter, rich mixture burns cooler. The default values I think are C0 = 5, C1 = 6. Making middle cylinders 2&3 run a little richer can equalize temperature. If you didn't do valve lash adjustment yet - you should do it before TBS.

 

[jomor147]

I have measured fuel pressure at 2.7 bar. If the pressure gauge reads correctly perhaps I should adjust C0 leaner ? I am a bit confused why the default values (calculated with fuel pressure at 2.5) are not zero ( or zero for c0 and let's say 5 for c1 ). How are the correct values determined (somewhere I read that they affect only low rpm) since we do not know the values of long term fuel trims, if the O2 readings are in spec etc. How can we determine if the fuel ratio is adjusted correctly. Anyway apologies if I hijacked the thread.

 

[Gary in NJ]

In my opinion the fuel trims have to be adjusted with a wide-band exhaust probe. Otherwise you’re just guessing.

 

[tuning-forks]

The default values I think are C0 = 5, C1 = 6.

I am a bit confused why the default values (calculated with fuel pressure at 2.5) are not zero ( or zero for c0 and let's say 5 for c1 ). How are the correct values determined

I have been through the factory and Haynes manuals every which way and I can only find how to change the value, but not what the default should be. No where do I see any specification for the default value.
What am I missing?

 

[grahammarsden]

As far as I have seen, from many posts about this, there *is* no "default value".

Presumably they're set at the Factory, on an engine-by-engine basis, but how they might do this, I have no idea.