[Mk2] [Turbo] Knock sensor issues driving me mad

[mr2turv]

Hi, I Got the knock sensor error code 52 about a month back and I hadn't changed anything at the time, so I assumed the sensor was bu88ered and I needed to replace it. Replaced it with no joy. So I ran a new wire from the sensor to the ecu, still no good and keep getting the light come on after driving it above 2 and a half k revs. Done a bit of digging and i'm still scratching my head over this. The wire I used was not shielded so i have bought some new cable and will retry with that but am fearing that it will not change anything. I would appreciate any advice on this as I have just taxed mot'd and insured my 2 and am not driving it

Thanks in advance, Mark.

[Peter Gidden]

You replaced with a new sensor? Or s/h unknown condition?

[mr2turv]

Bought one off eBay it was from gtschris though

[Peter Gidden]

Well i'd say you either:

Have two duff knock sensors
or
An issue with continuity from knock sensor plug to ECU (just check with a DVM)
or
Knock

[mr2turv]

Ok thanks how would I check Continuity with a multimeter as I don't know much about electrics, I only use it to check voltage supply to audio systems and stereos stuff like that

[dantheman]

Ok thanks how would I check Continuity with a multimeter as I don't know much about electrics, I only use it to check voltage supply to audio systems and stereos stuff like that

Theres a setting which is normally symbolised by a diode image and radiating sound waves, like the wifi signal symbol. Thats to signify its a buzzer. If you tap both probes together it will make a noise. So you put one probe at one end of the wire, the other probe at the other end and if you get a noise it means theres no breaks in the wires and the probes are effectively touching

[mr2turv]

Thanks a lot I've tested the wire and it's fine so I'm really baffled by it at the minute is there no way you can put a current through the sensor and tap it with a spanner and see if the multimeter changes to see if it works?

[mr2turv]

Finally got it sorted! Rewired the sensor back to the ecu and used the proper cable and put it in some conduit to make sure there is no pick up from surrounding cables. So to sum up I'm guessing the original Toyota cable has either corroded, been pinched somehow or picking up current off another cable somewhere. Lesson learnt: don't go buying expensive sensors before you know you can rule out all the cheap things lol.

My mr2 was winterised so only just got it back on the road last week to find i had a knock sensor problem, just been out for my first drive (in the rain) and i forgot what a machine these cars are! Thanks for any advice given it's really appreciated