Al Hounos

I remember it being described as violent back and forth twitching.

I'm asking because I have no knock sensor and I've seen it wiggle a little at about 10in vacuum and 3000rpm, as it's passing from 50-60psi. I doubt there is knock, I think my gauge is just a little sticky. As far as I know my engine has never detonated since the turbo went on.

Who has seen detonation through the oil pressure gauge?
More importantly, has anyone had detonation and didn't see it in the oil pressure gauge?

bripab007

To be honest, I've never really had a chance to look at my OPG while doing pulls on the street; just too much else going on. If it does move while pinging, it's never been violent enough to catch my attention.

flashlegs

I have seen knock on mine. I remember thinking it wasn't as "violent" as I thought it would be. Twitches would probably be a better word for it.

Ben

iTrader: (33)

I think it would be really obvious on an electronic gauge or if datalogging. The knock event is too quick for the mechanical gauge to freak out too much.

brgracer

iTrader: (14)

Unfortunately, once while doing a rough tune, I heard some knock and did look down at the OPG. It is much more than a wiggle. I would not say violent, but the gauge distinctly flicked to the right and back rapidly moving a good amount. Pretty hard to miss if you are looking at the gauge.

Braineack

iTrader: (62)

looks like its twitching back and forth.

bripab007

I'd rather spend my sensory energy listening for knock so I have the ability to keep my eyes on the road

TurboTim

iTrader: (9)

Why would knock affect the oil pressure gauge?

Braineack

iTrader: (62)

The 90-94 oil pressure sensors are carbon resistance sensors. As the carbon is compressed, the resistance changes. Detonation shock waves travel through the carbon sensors with massive changes in resistance that is indicated by the gauge needle flickering wildly to the left.

bripab007

I'll tell you one thing, when I was running an open downpipe for about a week, my oil pressure gauge, water temp gauge and tachometer would all go bonkers when I romped on it. I guess the soundwaves coming out of the downpipe were enough to make them all go a little nuts.

TurboTim

iTrader: (9)

Ahh no ****, I didn't know that. Interesting.

I do know that crusing the highway my oil pressure bounces around my 1.8 (with 94 sensor). I figured the sensor was bad and was going to change it with a spare. Maybe it's knock! hahaha.

Braineack

iTrader: (62)

hahah, maybe.