out of the blue knock

[86WH1turbo]

Hope someone can help. Car has been together now for a few hundred miles and everything was fine. I took the car out yesterday and now I get knock under normal acceleration (0 boost) each time the trans shifts. I have checked the DP and it is close to the frame but not hitting, have poly mounts both sides and the trans was just redone and everything is tight.

Knock shows on casper gauge and I get anywhere from 1.3 up to 5.6 on the scanmaster. The temps were a good deal cooler yesterday than in the past and I am running a TT 5.6. Any advice would be appreciated

 

[GNDriven]

What is your boost setting?

To get a better idea if this is transition knock or not, I would take it out on the highway and place it in manual third. Easy down the throttle and watch the boosy guage and knock guage. As the engine climbs in rpm and achieves max cylinder pressure. If no knock is detected, try it again in second gear. Still no knock, then try a 1st to 2nd gear change under boost. If knock occurs, it is something mechanical and not a pre/post detination.

A single knock event that is detected by the Caspers knock guage will light a LED for 4 seconds. The ECM meanwhile has allready went through its knock programming. If knock is brief the ECM will pull timing and then quickly add it back. So a single transition knock event will not totally kill performance.
but maybe shave off a 0.1 in the quarter. But try and locate it if possible.

 

[86WH1turbo]

My boost is set at 15. Thing is though it happens with no boost and under normal acceleration. It deosnt happen every time but I would say 8 out 10. I have had the car out several times since eveything was done and this just started yesterday.

I will give it a try on the highway as soon as the weather breaks again. Thanks

 

[mygn276]

Cut your oil filter open and check for bearing matl. Not saying that is the problem :wink: