Up to 15* knock on startup. Slowly backs back down to 0. (Within 7-8 seconds) This normal? Maybe prob. with cranking VE?

 

TTT Anybody?

 

Nope its not normal, looks at a few of my logs, never seen knock on start up.

Wouln't know where to look, if it dosn't knock at any other time its strange to see it on start up. In the stock tune the knock sensors dont read unless above 1.99% throttle

 

http://www.hptuners.com/forum/attach...0&d=1156691364
Link to log.

 

http://www.hptuners.com/forum/attach...0&d=1156691364
Current tune

 

There is a minimum timing table, if you set it too high it may do that also.

 

Where's this table located?
How about initial adder vs. ETC or IAT. Even though mine looks in line with other bins I looked at.

 

TTT Help wanted. Just noticed startup flare. Could that be causing this?

 

I know you've got a forged motor, but do you get any sort of piston-slap or other noise before pump-up or warm-up that might cause it?

 

Not noticeable at all. Sounds quiet when its started.. I would never of guessed it had startup KR without a scanner.

 

TTT Once more

 

is the header hitting the floorboard??

mine was doing that..

mark

 

No, I dont think so. As shown in the log, it's only doing it directly after startup. At the same RPM's anytime but startup its not getting that kind of KR. I dont know how to handle this.

 

TTT Again

 

With some year and model GMs, it is normal to hear knock at start up. Wish I knew which years and models did this but I don't. GM does an engine diagnostic proceedure by over-advanceing the timing at start up to cause the knock sensors to activate. If they did not activate, a check engine light and a knock sensor code was set. On some cars it was more audible then others. I've had a few C4/C5 Vettes that have done that and our 02 6L Escalade does it very loudly.

 

The odd part is its completely unheard. You'd think at 15* I would hear something before hand?

 

have you ever adjusted your idle park postion airflow table, i had the same problem and putting it back to stock fixed it..........