Miata Turbo Forum - Boost cars, acquire cats.

Miata Turbo Forum - Boost cars, acquire cats. (https://www.miataturbo.net/)
-   General Miata Chat (https://www.miataturbo.net/general-miata-chat-9/)
-   -   What does knock look like on the 1.6 oil gauge? (https://www.miataturbo.net/general-miata-chat-9/what-does-knock-look-like-1-6-oil-gauge-5872/)

Al Hounos 11-29-2006 05:52 PM

What does knock look like on the 1.6 oil gauge?
 
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 11-29-2006 06:10 PM

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 11-29-2006 06:17 PM

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 11-29-2006 06:31 PM

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 11-29-2006 08:05 PM

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 11-29-2006 08:54 PM

looks like its twitching back and forth.

bripab007 11-29-2006 11:09 PM

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

TurboTim 11-30-2006 08:56 AM

Why would knock affect the oil pressure gauge?

Braineack 11-30-2006 09:33 AM

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 11-30-2006 10:39 AM

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 11-30-2006 11:35 AM

Ahh no shit, 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 11-30-2006 11:41 AM

hahah, maybe.


All times are GMT -4. The time now is 07:35 PM.


© 2024 MH Sub I, LLC dba Internet Brands