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my knock count is 6 (at idling)

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the repair on the car's gearchange cables has completed.

today, after connecting the battery again, we did a Freescan at idling about 5-6 minutes after starting the engine

getting "knock count" = 6 (everthing else is perfectly normal)

*I never have this reading before??

I have not driven the car today as I was only short staying (too busy at work) and leave it at the car shop for few small touchup.

I will pick up the car tomorrow evening after work, and plan to reset the ECU to do a complete "learning process"

what's the reading of "knock count"

I have read the post by Artie, mentioning it's about air/fuel mix??

my car has upgraded to higher capacity primary and secondary fuel injector, has BOV installed, standard factory fuel pump and fuel filter, the air-intake is original and using K&N air filter, ECU is PUK #3 (higher torque),

exhaust is X180R spec with Cat. from PUK, running electric water/coolant pump, and turbo is ceramic by WC Engineering

anyone can give me some idea? THX

Edited by esprithk
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Did you start Freescan before the car? If so, the knock count if from the engine starting and is expected. So long as the number isn't increasing while the engine is running you'll be ok.

It will only increase under high load at 'knocking' is pre-detonation of fuel and you need things to be very hot for that to happen. The sensor is basically a microphone embedded into the block to pick up the sound of the detonation which is fuel igniting while the piston is still on it's compression stroke.

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Hi, Bibs,

I read the menu.

It says that if some object is hitting the engine block near the knock count sensor, it also will pick up signals.

so I must check if something is hitting the engine block first to eliminate this possibility.

and I do the Freescan after staring the engine, not before

Edited by esprithk
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I had a problem with fake knock for 2 years - to the point the ECU was retarding the ignition and crippling performance.

I replaced my knock sensor - it made no difference (Bibs still has my old one I think).

Ultimately the problem was traced back to the connector on the top of the knock sensor. If the connector doesnt home properly (and they can wobble - its a plastic clamp) on the sensor you can get phantom knock.

I replaced the stock connector with a segment from a PC power Molex connector - and from then on the knock count has been nil except when you turn the ignition off.

Also of note, if you remove the knock sensor, it must be replaced in the block dry on clean, unoiled, ungreased threads. According to Lotus technical, greased threads prevent proper grounding which is achieved through the knock sensor.


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ok, I picked up my car after work at 7pm.

It turns out that yesterday was probably some kind of software or signal error.

Because today the car is perfectly fine!!

(1) just apply the ignition, knock count = 0

(2) start up engine, at idle, parking, knock count = 0

(3) ok, after 5 minutes warming up to 80degree temperature, start driving.

* I took the long way, no traffic, no traffic light, long long high speed highway.

one way I keep 80km/h, the other way, I step hard to try out the boost

the knock count only picks up 2 in 1st drive, and pick up 1 in 2nd drive.

so I think my car is alright, just like before.

Thank you for your help!

Sincerely Eric Wong

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