knock sensor - can it be removed??

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Fizzy

knock sensor - can it be removed??

Post by Fizzy »

eh?
Fonzy
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Re: knock sensor - can it be removed??

Post by Fonzy »

yes matey just unscrew it! :wink:
Fizzy

Re: knock sensor - can it be removed??

Post by Fizzy »

let me rephrase that....can it be permanantly removed from the car?
Fonzy
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Re: knock sensor - can it be removed??

Post by Fonzy »

YES OF COURSE U CAN MATEY! BUT!!!! why would u want to go unprotected unless you got a different way of measuring knock! :?
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Re: knock sensor - can it be removed??

Post by gtschris.com »

fizzy. wrote:let me rephrase that....can it be permanantly removed from the car?


The ecu uses the knock input as part of a clossed loop ignition retard system.

The ecu looks at the input from the knock sensor, pull timing if necessary, then looks at the input again to see if the engines back in tolerance.

Our ecu friend is constantly adjusting and reviewing to keep the knock input in check............... unless you pop the sensor then the ecu will chuck a 52 and go into limp mode.
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raptor95GTS
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Re: knock sensor - can it be removed??

Post by raptor95GTS »

gtschris.com wrote:
fizzy. wrote:let me rephrase that....can it be permanantly removed from the car?


The ecu uses the knock input as part of a clossed loop ignition retard system.

The ecu looks at the input from the knock sensor, pull timing if necessary, then looks at the input again to see if the engines back in tolerance.

Our ecu friend is constantly adjusting and reviewing to keep the knock input in check............... unless you pop the sensor then the ecu will chuck a 52 and go into limp mode.


but if you unplug it from the block but keep it electrically connected it will surely read everything is ok?
BenF
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Re: knock sensor - can it be removed??

Post by BenF »

In short, with no (or a dead) knock sensor the ECu will go into limp mode, and the car will run really sluggishly ...

So yes, do you need a knock sensor on a Mk2 Turbo.

B.
Fizzy

Re: knock sensor - can it be removed??

Post by Fizzy »

ok...is it enough to alter the timing to 4 deg b4tdc?....we might just be getting there...... :(
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Re: knock sensor - can it be removed??

Post by raptor95GTS »

BenF wrote:In short, with no (or a dead) knock sensor the ECu will go into limp mode, and the car will run really sluggishly ...

So yes, do you need a knock sensor on a Mk2 Turbo.

B.


but if its still electrically connected, just not in the block then surely it will read 'no knock' for ever????
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Re: knock sensor - can it be removed??

Post by BenF »

allan welsh wrote:
BenF wrote:In short, with no (or a dead) knock sensor the ECu will go into limp mode, and the car will run really sluggishly ...

So yes, do you need a knock sensor on a Mk2 Turbo.

B.


but if its still electrically connected, just not in the block then surely it will read 'no knock' for ever????


There's knock, and normal engine running 'noises' which the knock sensor picks up - that's how it works. It detects if the sensor is dead by checking the output at 2500 rpms, and if there isn't any it throws a check engine light and puts the ecu into limp (massive overfuel) mode..

With it disconnected, its like having a dead knock sensor.
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Re: knock sensor - can it be removed??

Post by BenF »

fizzy. wrote:ok...is it enough to alter the timing to 4 deg b4tdc?....we might just be getting there...... :(


Sorry, won't work. The ECU needs to see some output from the knock sensor in order to run normally.
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Re: knock sensor - can it be removed??

Post by MR2Mania »

allan welsh wrote:
BenF wrote:In short, with no (or a dead) knock sensor the ECu will go into limp mode, and the car will run really sluggishly ...

So yes, do you need a knock sensor on a Mk2 Turbo.

B.


but if its still electrically connected, just not in the block then surely it will read 'no knock' for ever????


I don't think so, because it looks for "noise" on start up to know that it's working. However, if you run a standalone, you don't need it! ;)
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Re: knock sensor - can it be removed??

Post by raptor95GTS »

MR2Mania wrote:
allan welsh wrote:
BenF wrote:In short, with no (or a dead) knock sensor the ECu will go into limp mode, and the car will run really sluggishly ...

So yes, do you need a knock sensor on a Mk2 Turbo.

B.


but if its still electrically connected, just not in the block then surely it will read 'no knock' for ever????


I don't think so, because it looks for "noise" on start up to know that it's working. However, if you run a standalone, you don't need it! ;)


that toyota ecu is too darned clever sometimes when you're trying to fool it :shock:
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