I was wandering if anyone with OBD 2 readers like the digimoto have checked for codes even if your light is not on? I have a constant code P0328 which is for excessively high voltage form knock sensor, I have had it for a while even before the TT install and had not paid much attention to it since the light wasn't on and I really didn't notice any difference in performance.

We were trying to tune another TT and just couldn't get the power considering we were using what I have in mine and decided to check the ECu and found the same code plus P0327 which is excessively low voltage so I assume his timing was just all messed up causing the problems.

So based on this I decided to log my timing using the digimoto and although it is not the best logger I did see my timing in at WOT around 15 or so, assuming stock timing is 27 and I am pulling 6 degrees at redline and full boost this means the ECU is pulling another 6 degrees or so, which might also explain why I am only at 401 at 8 psi while others are at 420+

SO if anyone else has this please post and any thoughts as to why, as I type this it occurred to me I have the UR Crank Pulley so I wonder if that is causing it?

 

Use higher octane fuel, and try again (unless you were already using 100 octane). See if this is mechanical noise, etc., or fuel induced retarding.

 

I would go that route if I thought it was actually knocking but I would think that from the code that it would be a wiring or sensor issue being that it is excessively high because if it was mechanical or fuel I would think it would just work normal and retard when needed and if taken outside the normal range to get it to excessively high I would hear the knock at that point?

 

Could a knock sensor fail with the voltage output high and if it can fail in this mode then wouldn't the ECU pull timing thinking it's a valid signal?

 

That was my thought like going into a "safe" type mode so I was wandering if others have this code and might explain why some have lower results than expected at the dyno and not know about it since the CEL doesn't come on just gets the code stored.

 

This....digimoto..[ never heard of it ] Does it read what the ECU is doing ? If so , than your ECU is retarded timing to 15 degree's and you are pulling another 6 degree's . My OBD2 reads only what the ECU is doing and not what my piggyback is adding to the mix. When my wiring was messed up . At WOT , the OBD2 was reading 15 of timing advance . It was getting a false reading from the CAS wire [ knock ] . PLus my piggyback was reducing the timing also

 

AHHH good point, I was assuming the digimoto was reading final timing but you might be right then I am really low, the www.digimoto.com just plugs into the standard plug in the car so it should read whatever other readers do.

 

After the wiring was straightened out the car really woke up . Now the OBD2 reads 22 degree's at WOT and actually goes up to 24 degree's after 6500rpm

 

What was wrong with your wiring and what fixed it?

 

the shop used clips to connect my CAS wire and my Zeitronix