VR KNOCK Sensor

[dav 0]

When the knock sensor on a VR or any car for that matter kicks in and retards the timing does it feel like the power is being held back and like the motor is bogging down?

 

Thanks

D.

[Guest]

Yes it does lose power but it shouldn't be great amounts. Thek nock sensors (plural) listen for detonation and when they hear it retards the ignition 3 degrees and then advances it one at a time until it hears detonation again and retards the timing and goes through the cycle. So it will feel a little slower but it shouldn't be too bad, what is yours doing?

 

Cheers, Dennis

[dav 0]

Hello,

 

When I put my foot down or when pulling out of a junction it kind of goes flat and does not seem to want to rev. Then it all seem fine it only tends to do this under load.

 

Thanks

D.

[dr_mat 0]

Sounds more like a misfire..

Does it do it worse when the engine's cold or hot?

Does it run better on part throttle?

[dav 0]

Runs better when the engine is hot,

and runs better when on part throttle

 

D.

[Guest]

It is probably not the knock sensor, check the plugs, cap, rotor, leads, vaccum leaks, blue temp sensor, air filter, O2 sensor, and leaks in the entire intake system. If it running poorly then the problem is not timing related but a mechanical failure. Ignition parts can easily cause this like a dying coil or leads that are shorting out.

 

Cheers, Dennis

[dav 0]

Well thats the strange thing about it,

I have just changed:

Blue temp sensor, Coil,Rotor Arm/cap, HT-Leads the filter is new'ish and the Lambda Probe.

I could change the plugs but they must only have about 3.5K on them

from what you say it seems like it may be a vacume leek....i hope

 

D.

[DierWolf 0]

Having the exact same problem but mine occurs only on hot days, rainy days it doesnt happen at all.... Bogs down over 2K rpm, actually have to pull off the road, play with the throttle for a while then it catches itself again and runs fine.

 

I too have changed plugs, wires. dont believe it has to do with any of those because the car runs perfect on cool / rainy days. Runs like crap on hot days and engine temps are well within the norms.

[Crasher 3]

I have had the early air mass meters cause this.

[-Neil- 0]

I have problems that sometimes when setting off from junctions or driving along and the car is underload, when i put my foot down, the engine dies, completely, no power and the engine stops, car still rolls tho, and the suddenly, the engine will cut back in, once i did pull over and the engine just reved up and down to near stalling point, then caught itself and came back then nearly cut out again, i pressed the throttle but that didnt help or change it doing what it was doing.

 

Would this be the same thing?

[Roger Blassberg 0]

I agree with Crasher - look at the MAF. A VAG-COM session may tell you if it has failed completely, but the little tinkers can also just deteriorate without total failure and not give a VAG-COM message.

 

Best wishes

 

RB