Help with knock-


Feb 24, 2005
I have not touched my GN in 3 years. -Aside from starting it every other month, keeping battery charged.

Come summer, trying to get it running again.

Changed oil+ZDDP/filter/CR43TS gapped@.030/.032 / MSD 8mm wires.

FP was 42# with line off, using TT chip burnt for my 60# Motron injectors.

Boost is limited now to 18# using an digital controler, but the knock will come well before I even try WOT.

I tried adjusting the Methanol to spary at a lower onset - Nothing.
I added 2-3#'s of fuel - Still knock.

BLM is running down in the 110s, so it is rich, still knock.

Car was fine before I took it off the road, now it seems like she is not too happy.
Does it knock if you have it in park and rev the motor a bit, or only under load?
Something like this happened to mine years ago. With a glove!!...and the engine warm and running, try opening the EGR valve (you squeeze-up on the underside). If it does not affect the way the engine runs, your EGR passage in the intake manifold may be plugged with carbon. In which case you will have to pull the plenum and clean it out. If the engine dies, not the problem.
No knock in park, only under load. Drives just fine without any boost.

COPO TOM: my EGR system constists of a chunk of iron in the heads. (not there).

So even under rich conditions the boost is making knock, with an extreme octane from the 93 pump and the M1(~115octane) making around 104octane... should be fine for my load conditions... but the car just wants to hate me.
Yep, got an external guage showing 1psi/1lb of fuel.

The car wouldn't be fun if it ran perfect all the time!