knock sensor CEL when its cold

[dorifuto.boi]

heyy guys

so over winter, my cel stayed on with the knock sensor circuit malfunction bank 1. i forgot the code lol.

there was one day a couple of months ago when it warmed up to like 20 degrees and when i went out for a drive, the cel didn't come on when i started the car.

everyday after that, the cel came on after starting the car (the temperature droped back down to under 10 degrees)

then today, it is so warm out. its like 26 so i decided to go out for a drive again. and when i started my car today, the cel didn't come on either !

what the heck -.-. does anyone know why ?

[fenixus]

may be a false lead, but check resistance between terminals of ECT for EFI sensor (2 wire plug, right next to "rad" cap) when car is dead cold (parked for at least 8 hours) on a colder day.

your ECT sensor may be misreporting which fools the ECU into wrong air/fuel mixture on a cold day when started cold ... and in result causing a knock

[dorifuto.boi]

well on those cold days, even after my car warms up, the CEL remains on.

also on those cold days, right after i start my car and its in the "warming up phase" the afr stays around 12.5 but the knock sensor circuit malfunction bank 2 still comes on.

but i will check resistance when i get some time

[dorifuto.boi]

well its no longer freezing cold but the cel came back on again and is staying on. i checked the resistance on the ect sensor and it reads according to the graph.

Knock sensor CEL does not come on because the engine is knocking. It only comes on because the ECU is not receiving a signal from the knock sensors. Is that correct ?

My bank 2 knock sensor CEL comes on and off. That means my knock sensor is dying correct (or the wiring is bad) ?

Does excessive knock cause knock sensors to blow ?

What else can cause the knock sensor to blow when its in the engine ?

Thanks a lot,
d

[fenixus]

you are correct, the knock sensor error code means there is signal loss between knock sensor and ECU, check the sensor and wiring. if replacing this sensor, go with OEM, ECU is very picky.
make sure the wiring is nor damaged somewhere (broken or shorting).

Originally Posted by dorifuto.boi

well its no longer freezing cold but the cel came back on again and is staying on. i checked the resistance on the ect sensor and it reads according to the graph.

Knock sensor CEL does not come on because the engine is knocking. It only comes on because the ECU is not receiving a signal from the knock sensors. Is that correct ?

My bank 2 knock sensor CEL comes on and off. That means my knock sensor is dying correct (or the wiring is bad) ?

Does excessive knock cause knock sensors to blow ?

What else can cause the knock sensor to blow when its in the engine ?

Thanks a lot,
d

[Chris Crash]

Replace the sensor ONLY WITH OEM. Nothing else. OEM is Denso, so if you find a shop selling Denso brand. There you go.

Try that first. Then check wiring. Then check ECU.

[a94autoCamry]

aren't you boosted?? If you keep blowing your knock sensors, replace them using the GM ones (less prone to blowing, as the Toyota ones are really sensitive when it comes to boost)

[dorifuto.boi]

yeah, im gonna check my wiring and replace the knock sensor with an oem one. but before i do that, i would just like to know what causes them to blow.

yeah im boosted and everyone uses gm sensors on their boosted cars and i know i should. but im stubborn so i really want to know why the stock ones blow before i switch over to gm.

do knock sensors blow because of too much knock ? if so, then a good tune should fix that and i wont have to use the gm sensors

or do knock sensors not blow because of excessive knock but because of something else ?

or maybe they blow because of excessive knock AND something else ?

thanks,
d

[Chris Crash]

Well hopefully you're not knocking period. Maybe it's ping? Try higher octane maybe.

Also, relocate the sensor. That should help tremendously.