VEMS Ign. Table, how much advance ?

[th.b.w.]

Sorry, i can't see any vems / magatune maps....

Thomas

[Jamo]

specsavers.........................

http://www.efiexpress.com/catalog/ar...?articles_id=1

Bottom of page, download tuning software http://www.efiexpress.com/downloads/....1.27_audi.zip

[th.b.w.]

Holy shi.....t,

a spark plug (Bosch F5DPOR) isolation was broken, has damadged a ex.valve, burned 2-3mm out of the steel, now i run only 4cylinders.....

came it from to agressive ign.timing ?
or high egt's (i haven't seen) ?
or fault spark plug ?

Thomas

[A80Avant]

very unfortunate, seems likely a spark plug malfunction.

[A80Avant]

how much torque did you have on the spark plugs?

[th.b.w.]

Hi,

not more than 15-20NM.....

[A80Avant]

hmm. it says 30Nm in the manual. Of course it may have nothing to do with it

[th.b.w.]

Don't you realy think it comes from too much ign. advance ?

Thomas

[A80Avant]

no i dont. I have more timing than you if i judge from the map, from day one, and havent had a problem. Of course the compression ratio is different but very small difference. Also i have seen other maps with even more aggresive timing. I think its just bad luck and unfortunate cause i recently read another broken bosch plug...Is the quality going bad here?

[th.b.w.]

Hi, so i have removed the head.

There is no point to say that there is knock.

All Pistons and heads look pretty good without any pinging or melted aloy....


Thomas

[a4kquattro]

Hi, so i have removed the head.

There is no point to say that there is knock.

All Pistons and heads look pretty good without any pinging or melted aloy....


Thomas

you cant necessarily tell from just looking at the top of the piston that there is no knock. how is your compression? one of the first things to take a beating are the rings and the ring lands on the side of the piston as the high pressure spike from knock pushes on the rings.

[th.b.w.]

Hi, the first look wasn't right....

I have cleaned the pistons and head, now i see pitting on cyl. 4 more and a little bit on 3 .
I wonder that it is only on the intake side.....

Now i will check the injectors and send this to a flow tester....

I think the cyl 4 is the hottest, is there an possibility to adjust the cyl. selektiv with VEMS to run these a little bit richer ?

Tomorrow i will rebuild the valves ...

Thomas

[A80Avant]

mine should definitelly have some pitting as i have heard it while tuning! but dont forget that engines can endure knock for fairly long period of times. Its preignition that will shatter them. And that can also come with very low timing as well.

[Jamo]

I think the cyl 4 is the hottest, is there an possibility to adjust the cyl. selektiv with VEMS to run these a little bit richer ?

Tomorrow i will rebuild the valves ...

Thomas

Yes in the higher firmwares injector trimming per cylinder is available

[A80Avant]

would that be a solution for 3d cylinder which usually gets hotter then? just to keep it slightly richer? sounds a good idea. Has anyone tried it?