C20XE Knock Sensor?

[Spectralcav]

My engine doesn't seem to be running right - it's OK if you gradually apply the throttle, but seems restricted if I put my foot down too quickly. There is a noticeable difference in power above 3500rpm, but anything below that it bogs down really easily. Hope that makes sense!

I read somewhere that this kind of symptom can be down to a faulty knock sensor, and as that is relatively cheap and easy to change I'm thinking that might be worth a try. What do you think?

Engine is regularly serviced, air filter is clean, fuel filter is only a few months old and exhaust has a decat pipe fitted.

The engine management light doesn't come on at all except before starting the engine - it goes out as soon as the engine is started. Would a faulty knock sensor register a fault code or is it like the CTS which doesn't seem to...

Any thoughts?

[planetc]

knock sensor usually registers a code, have you looked at the intake pipe from throttle body to mass meter?

[Spectralcav]

knock sensor usually registers a code, have you looked at the intake pipe from throttle body to mass meter?

Had a quick look a couple of days ago - will have a proper look today.

It's not idling right either. Thinking maybe the intake manifold is either leaking or gummed-up.

Does the ICV have any effect on general running or just idling? I've never cleaned it in over 10 years as it's never caused a problem before now.

[Spectralcav]

Well, the intake hose is AOK from filter through to SFI box - shame really; was sort of hoping for an obvious fault...

Will try spraying WD40 round the intake manifold tomorrow.

[gsi pie]

spray wd40 down the ICV pipe

its the one thats comes from under the SFI box

i did this on mine and it sorted it (my icv was sticky revs use to hold now n again)

just an idea dude

[Spectralcav]

spray wd40 down the ICV pipe

its the one thats comes from under the SFI box

i did this on mine and it sorted it (my icv was sticky revs use to hold now n again)

just an idea dude

I'll give it a go!

Would you do that with the engine running?