Faulty knock sensor on 93 J30 or User Error?

[robmcole]

I had a question about the J30 knock sensor, I have a 93 J30 with 93k miles. It seems that whenever the engine is on heavy load (hard acceleration in a high gear), I hear a ticking from 2k-4k rpm. It stops above that. I thought the J30 had a knock sensor, but maybe it is not functioning properly. I use 93 octane gas. Tell me if there is a way to run a diagnostic on the knock sensor. All I have done to the car is install a "drop in" K&N filter, and have a highler flow catalytic converter. Maybe this has changed what the stock computer's fuel/air map is programed for. That is the only theory I have.

-Rob Birmingham, AL.

[IvoryJ30t]

if the knock sensor was bad you would have very sluggish power, bad gas mileage, and also most likely a CEL.

knock is more of a "beating the engine with a hammer" type pinging, not really a "tick"

[robmcole]

Well, let me rephrase, It just does it between 2k-3k rpm. It is just annoying, and I want to make sure I am not doing damage. I am getting bad gas mileage, but I think all J30's don't get Geo metro mileage (ha-ha). I get around 17mpg. I don't have sluggish power, so maybe all is good.

Thanks for the response!

-Robert Cole Birmingham, AL.

[IvoryJ30t]

does it tick when its cold and idleing, and go away when it warms up?

[robmcole]

No, it is a constant thing. from 2k-3k rpm. Cold or hot. Maybe a little more noticable when it is warmed up. My backup theory is that I have a gasket leak off the headers. I might need to buy some new gaskets to see if that is it. It is hard to pinpoint where the noise is coming from.

-Robert Cole Birmingham, AL.

[Q451990]

You won't have a "Check Engine" light on a 93 model for knock sensors (unless maybe it has the CA emissions package). You need to have someone who knows what they're doing run a full array of tests with Consult. It's probably time for an intake cleaning, plenum cleaning, injector flush, etc. Has the timing belt been replaced yet?

Luckily you aren't too far from Atlanta and T3. I'd make the trip vs. messing around with questionable local sources. Shouldn't take you more than 2-3 hours.

Also, bad knock sensors will send the car into a "full protect" mode as if the sensors were detecting knock - so even if they're bad, fixing the knock sensors wouldn't fix the knock.

Heath

[VimyJ]

You should be getting over 20mpg for typical city/hwy drivng. I get ~22+ mpg 66% hwy 33% city.