DIYPNP 99-00 timing changes with rpm
 

Hi,

today I set up my DIYPNP and adjusted the trigger angle (came to 3 degrees).

I noticed that with the fixed angle still on - it wanders from the set 10° at idle to about 6° with rising RPM. I tried the hardware latency but that didn't change everything.

Any idea?

Thanks

Sven

Just some information for the DIYPNP crowd.

Matt @DIYAutotune gave me the advice to desolder C28 at the Microsquirt Module - they noticed that the C27 gives problems with phase shifting and are sending out the newer DIYPNPs without C27.

Just for you to know - I thought it could be useful for some...

@Ben - did you notice something like this?

No, I didn't notice, but also no, I didn't check.

Eeeps, I would certainly check! Not that you can't technically make up for it with your map, but it's sloppy.



Frank,
You don't get an adjust with timing latency? No change at all?! That's positively weird. Unless maybe C28 is on the output? I guess it still shouldn't matter.

What RPM are we talking about? 6,000 RPM = 100 hz = 36,000 degrees per second. 3 degrees = 83 us. How much latency did you try?

Abe, I didn't check with the stock sensor inputs. I did check the trigger wheel. It's good.

Hi Abe,

I am not Frank, but - us Europeans, we are all the same anyway...:laugh:

I did only try very small latency - like the one you used to set in you maps ~6

I have seen the 4° phase shift at ~4.000 rpm. But it did seem to go up to ~4° and don't move much after that.

I am going to try the C27 mod.

Greets

That is very strange. Keep me posted, I want to see where it goes.

Sorry, I have to admit, I did think "Europe" and stop thinking there. :-) 4* at 4krpm is even more extreme. I should check mine, I know it's kinda high.

:noob: - again.

I think the fault is - like so many times before - on my side. The huge timing change made me think if there could be another problem. So I had a look at the datalog I took, on the only ride up to now with the DIYPNP. (Because my car is in winter-sleep-mode now)

The timing seemed strange - the spark advance way lower than the value in the table. Had a look at knock retard (which was turned on) - knock retard of 10° all over the log... :noob: I must have mis-wired something from my knocksense ms to the input. That would explain the strange behavior.

Greets

FIY, I'd misremembered the capacitor number - it's C27.

Heh, I was going to suggest it but figured I didn't need to. I guess I was right. :-P