C20XE knock sensor fault

[staggy_gsi]

Right, got a fault on my XE corsa. Management light has been coming on and off for months, so I read the fault codes a couple of weeks ago and it came up with 'Knock sensor signal faulty'....

The wiring to it looks OK etc, so I bought a new one from Vauxhall and the fault still persists. The car made a healthy 147bhp last month (with the fault present) so I can't see the engine itself being knackered.

Anyone got an idea what else could cause the problem? Bit miffed at spending £35 on a new sensor like....

[Andy]

Is it clean where the mating face on the block is?

[staggy_gsi]

yeah looks clean enough like, not corroded or anything. theres no loose brackets causing vibrations nearby or anything like that either...

[Andy]

Does it still flash it up if its cleared after the ecu being unplugged overnight?
Is the plug ok??

[pie]

my mate had a knock senor go on his astra gsi and wouldnt rev past 3k

[staggy_gsi]

i can clear the code and sometimes it'll take a day or so to flash up again, but sometimes it comes straight back. runs worse when the light is on, pulls loads better as soon as the light goes out again.

[Will F]

It retards the ignition a few degrees as it thinks the engine is knocking! its usually a fault in the mini loom - swap that and see what happens

[staggy_gsi]

ah cheers Will, I'll see if i have a spare loom in the boxes of dismantled XE at work lol