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knock sensor?

Can anyone shed any light on the truth to oversensitive knock sensor?
I am not a big fan of disconnecting it and leaving it off, it is there for a reason.
But, I recently am having an issue with the way the car runs when it is hooked up.
I am not running anything crazy, I believe about 14psi, intercooler, base timing at 10-11deg, always 93 octane fuel.
This year, when I started driving the car, I notice that when I go into boost, once it gets a certain amount, the car falls over and just doesn’t really pull anymore.
I did an experiment and disconnected it, drove easy for a few days and no difference. Then I step on it and it runs great and continues to pull.
Begin on the month I was on fuel from last year, so I thought that may be a possibility, so I ran it down to quite empty. Filled up with new and repeat the process.
Seems to be the same issue, so fuel isn’t an issue.
Leave it off?

I leave the knock sensor unplugged. I think the knock system is too sensitive. You could try retarding the spark timing a few degrees but what fun is that ?

I had an '86 Mustang SVO that would fall flat. Disconnecting the knock sensor fixed it. I may have advanced the base timing a few degrees. I think of the base timing as something you should be able calibrate yourself.

Unfortunately, the Mustang SVO was stolen from my driveway. I then purchased an '88 XR4Ti new and immediately disconnected the knock sensor based on the experience I had with the '86 Mustang SVO. The XR4Ti went 90,000 miles before I replaced my 1st head gasket. I have yet to melt any pistons.

Clearly the knock system should work. It will probably extend the life of your head gasket, but at a cost to performance.

The knock sensor is an accelerometer tuned to around 7000 Hz. 7000 Hz is the frequency that should correspond to knock during combustion. The EEC-IV is supposed to compare the magnitude of the knock signal during the power stoke to the magnitude of the knock signal not during the power stroke. If the magnitude of the knock signal during the power stroke is greater than the magnitude of the knock signal not during the power stroke then knock is sensed. When knock is sensed, the spark is retarded and boost can be reduced.

It appears to me that the knock system detects knock when the engine is running fine and knock is not yet audible.

I have always thought that people worry too much about knock. When I hear a nice light knock, I figure my spark timing is just about right. My experience is with engines that are not pushing the limits of their capability.

I would say leave it off as I do on mine that's stock with an automatic. my other one i have it hooked up because i can tune the amount of timing it pulls. stock table is like 20 degs iirc.

one thing to add is the knock sensor can pick up valve train noise giving a false positive.
Mike K

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