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This is an audi inline 5 engine which has been running wasted spark for a long time, I fitted a cam sensor more recently and decided to try running sequential but the engine wont start.

the first trace is with all the spark plugs in and for the second i removed all but no 1.

You can see the cam sensor is triggered at exactly the same time as the missing tooth on the crank sensor, is this a problem and would it cause problems?

The flywheel has 15-1 teeth, here are some settings.

You can see in the trace with no 1 spark plug in the cam sensor and crank gap are two teeth btdc which works out to 48 degrees, this is the figure i put in the cam and crank settings.

The only discrepancy is when the engine ran wasted spark this crank figure had to be set to 35 degrees to get the ignition timing spot on. Its not miles out but i understand the cranking oscilloscope is just a guide for setting up and also my teeth on the flywheel are 24 degrees apart which could skew the results a little.

Just had a thought, will I need to add 100% to my fuel map because I'll only be injecting once every 2 revolutions vs once every revolution using wasted?

If you look in diagnostic display, it will tell you where it is seeing the cam tooth, you just need to manually determine in which phase.
Crank the engine, run the engine etc to see what it says.

When you have an indexed crank wheel, all spark timing, injection timing etc is 100% controlled by this, so you shouldnt need to change anything there.
The cam sensor just tells the ecu where cyl 1 is in relation to the 720deg cycle.



Most ecu's/suppliers dont like the triggers happening at the same time, but few actually prevent you from doing this.

What you can do to move the cam trigger slightly if you really must, is change the cam trigger edge setting.

I only changed from batch to sequential for a short period with mine, and at first I did increase the fuel maps, but pretty sure I ended up trimming them back to almost where they were before anyway.

Hi!

Maybe you are firing at exhaust stroke TDC, so try out to add 360 degrees to cam sensor position: 48--> -312

Best regards
Qgli

We'll I looked at the cam angle in the diagnostics and it told me 200 degrees, I suspected this to be wrong but tried it and it failed. I then changed the cam edge in sequential settings and this shows minus 31 degrees, this worked and the engine is now fully sequential.

Here is the oscilloscope test done after I changed the cam edge