Hi!
I am getting knock counts when idle driving and the aldl tells me that 1 and 2 cylinder gets knock counts at 800 rpm and 3200rpm where can i start my trubbleshoting,please let me now if you have any answers.
Thanks!

 

Read plugs from cyl 1 and 2 to help diagnose. In reality you shouldn't get knock counts under no load.

 

Too much timing or not enough fuel.
And you need to make sure it's not a noise that the ecm just thinks is detonation.

If it accurs during a transistion, then you need to pull some timing, or add some fuel to stop it from BEGINNING. If you just add fuel or yank timing at the exact spot you see the counts, you'll never get rid of it.

 

The TBI ECMs force knock as part of their diagnostic routines. The knock at 800 RPM may be from startup.

The knock modules (ESC module) used in the '88-'90 TBI setups are not that good and will report knock when there isn't any.

Is the reported knock random and scattered about in the MAP vs RPM range, or is it always in one location? What scan tool are you using?

RBob.