c25xe showing codes 16 and 31

[Dirtydog1]

ive got a corsa v6 and its running very flat and hesitant. all mouth and no go. ive got the flash codes up 16 and 31 rpm signal sensor/crankshaft sensor
and knock sensor bank 1.

is it a case of just buying these two sensors or will one sensor cause the other to mal function?

seems strange as ive just built an astra that is doing the same thing!!!! lol (same codes too)

the corsa has been running perfect for ages, the engine in the astra was untested prior to fitting so im assuming its been knocked around abit.


occasionally the corsa comes back to life and runs well again for a few days/weeks then it gets ill again, also if you disconnect the battery for 1 min or so it will run perfect for a few mins before returning to ill mode.

any one help me out? dont want to buy a batch of sensors if i dont need them.

Cheers

[John]

Rpm fault will always show till it's running iirc. I'd go for the knock sensor first. Cam timing ok?

[Dirtydog1]

both cambelts have been done, the corsa was running fine for months and started getting an intermittent problem for a while now its got these codes.
i did wonder about the rpm sensor, but also couldnt beleive a knock sensor would make it play up so badly. i guess it goes into hibernation mode.

[Dirtydog1]

also, with regards to the cambelts, the astra drives well if you clear the codes as does the corsa, then they come back on again :(

the corsa is more intermitant (cant spell it) though, it goes good then bad by its self.

[craig green]

fault codes for a particular sensor wont always mean the sensor is at fault, a chafed wire going to your crank sensor will show up as a crank sensor fault etc.

Cam timing does sound a sensible culprit, but disconnecting the battery etc wouldnt cure it temporarily.

[Dirtydog1]

im 100 percent sure its not cam timing on the corsa, its goes to well when its running right! as for the astra, it also goes well for a few mins after the battery has been disconnected.

what effect would a faulty knock sensor have on the engine running?

its weird how both cars have the same problem!

[craig green]

knock sensor adjusts the timing.

Run the engine to temp & knock the block with a large spanner, you should hear the timing change if the sensor is functioning correctly.

[Dirtydog1]

all sorted the rear knock sensor on both cars had chaffed through......weird but finally fixed. cheers

[craig green]

Excellent. Where do I send the bill? :)

[Dirtydog1]

lol, :)