need to know what these sensors do

Big_A_Cupra20vt

Active Member
Jan 4, 2007
184
0
margate
what is knock sensor 1? and why would i have a fault code logged about it?
i cant find a lot of info on this m other 2 codes i can find pretty much what i need but not this one, the fault code for it is 16712
 

Black TDI Turbo

Shussssh Its A Diesel ...
Oct 2, 2005
1,175
0
North East
knock sensor is located somewhere on the engine block and detects when the engine makes a noise, that it shouldn't, for example a misfire, normally comes up that fault on a diesel when its misfiring but petrols do have them.

16712 P0328 Knock Sensor 1 Circuit High Input

have you had a misfire recently if not check connections on the sensor itself and check the wiring.
 

Big_A_Cupra20vt

Active Member
Jan 4, 2007
184
0
margate
well a last week my oil pump was replaced as it got fooked and i thought i had killed the engine because of the noise it was making where it had run dry could this be the reason for the log?
 

Black TDI Turbo

Shussssh Its A Diesel ...
Oct 2, 2005
1,175
0
North East
they might have disconnected it when doing the oil pump and yet it could have been noisy so, id just clear it then recheck in a week or so just incase
 

Big_A_Cupra20vt

Active Member
Jan 4, 2007
184
0
margate
im getting it rechecked at the end of the week as another code that showed up was the brake switch esp light on dash but only after i fixed the stupid clutch pedal clip problem so i dont hink it is anything bad.
 

ganda_cupra

VW Commercial Technician
Sep 4, 2006
286
0
Near Sheffield
Petrols have them, put simply its so the ecu can advance the timing as far as possible before it starts to 'Knock' (also known as pinking detonation etc), when it detects 'knock' it retards the ignition timing. Basically allows the engine to run on its limit of ignition timing advance and hence run more efficiently.

Is the fault sparadic, sometimes has SP next to fault for sporadic, if so then it was poss disconnected, (but shouldn't log a fault unless ignition was on), I'd delete the fault then recheck in a couple of days time.

If it isn't sporadic, then still delete and check it in a couple of days. If fault code returns get it checked out or try a new knock sensor (around £30- £40 from dealers), just fit in right place as theres 2 of them and there the same i believe, also torque it down to the proper setting.
If it still has fault after replacing the sensor then I'd check the wiring?

What were the other 2 codes logged?
 
Last edited:
Jun 28, 2001
1,533
0
the knock sensor is made up of piezoelectric crystals, the sensors are torqued to a specific torque setting and to tight they pick up noises more. normally if you remove the sensor it is corroded behind forcing the sensor to become tighter and more sensitive,remove the sensor clean it and the block surface then refit and torque, should be all o.k. then
 
Last edited:
Jun 28, 2001
1,533
0
you can test them using a multimeter and shaking it it creates a voltage.
 

ganda_cupra

VW Commercial Technician
Sep 4, 2006
286
0
Near Sheffield
Don't see many faulty ones on the Vans at work, I've only fitted one in nearly 2 years on a T4 diesel/lpg camper. The majority are fitted with engine trays underneath to quieten the diesel knock though lol.
 

Big_A_Cupra20vt

Active Member
Jan 4, 2007
184
0
margate
the other codes are 18010 aparently this is logged if the battery is disconected which it was a couple of weeks ago so this one shouldnt show up again when i get it rechecked and the other is 16955 brkae switch i think this one flashes up the esp on dash but ive only had this happen since i changed the clutch pedal clip after the pedal hit the floor (common problem i think due to the crappy spot weldes holding the clip housing together.