sinister engine noise, im quite worried.

Hello guys I could really do with some advice.
I want to be sure whether it is knock or not and know whats going on inside.
Last night I had multiple misfire on all cylinders and a code on cylinder 3(the one that was popping up) they cleared and never returned after a drive so I assumed it was due to me pulling them out and checking plugs etc.

I really need to know what I should be monitoring in vcds, and what values mean what, ie, tell tale signs of knock, if it is that. What should i look for?
Knock sensors are doing something i know that, cf's didn't go very high at all. But then, i was reluctant to do a wot run to red line.

Any advice is massively appreciated, I'd love to prove its not detonation. Then i can worry a little less. I would have thought after fitting my catch can this would be massively reduced
 
Hello guys I could really do with some advice.
I want to be sure whether it is knock or not and know whats going on inside.
Last night I had multiple misfire on all cylinders and a code on cylinder 3(the one that was popping up) they cleared and never returned after a drive so I assumed it was due to me pulling them out and checking plugs etc.

I really need to know what I should be monitoring in vcds, and what values mean what, ie, tell tale signs of knock, if it is that. What should i look for?
Knock sensors are doing something i know that, cf's didn't go very high at all. But then, i was reluctant to do a wot run to red line.

Any advice is massively appreciated, I'd love to prove its not detonation. Then i can worry a little less. I would have thought after fitting my catch can this would be massively reduced
 
As above Block 20 shows how much the ECU is retarding the timing for each cylinder as a result of detecting knock on it.
 
So if I have very high values then it tells me there is knock? What sort of figures should I see or not see?
And thankyou

The higher figure, the bigger the knock.

The general rule of thumb is up to 6 Correction Factor (CF) is acceptable.

So, up to and including 6 is within tolerance.
 
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Example of a block 020 log:

Code:
Group C:	'020			
	
TIME				
STAMP	 CF	 CF	 CF	 CF
	0	0	0	0
	0	0	0	0
	0	0	0	0
	0	0	0	0
	0	0	0	0
	0	0	0	0
	0	0	0	0
	0	0	0	0.8
	0	0	0	2.3
	0	0	0	2.3
	0	0.8	0	2.3
	3	0.8	0	1.5
	3	0.8	0	0
	0	0	0	0
	0	0	0	0
	0	0	0	0
 
I take it this should be done at wot in 3rd to redline, niiiiice. I don't remember seeing very high values at all when doin the odd wot Sprint last night. I shall try again. Is there anythin else I could monitor?
Cheers welly.
 
I take it this should be done at wot in 3rd to redline, niiiiice. I don't remember seeing very high values at all when doin the odd wot Sprint last night. I shall try again. Is there anythin else I could monitor?
Cheers welly.

Depends what you want to find out bud. There are so many things that are useful.

Block 011 - Ignition advance and inlet air temperature.

Block 115 - Requested vs actual boost.

Block 118 - Actual boost and N75 duty cycle.

Block 002 - Mass airflow and injector on time.

Block 001 - Lambda fuelling adjust percentage live.

Block 020 - Idle Stabilisation (knock).

Block 032 - Short and long term fuel trims (Don't reset fault codes or else these will both be 0.0%)

Block 031 - Air-Fuel ratio Specified vs Actual (Wideband ECUs only)

There are so many that can be done, but those are the ones I use most often.

All logs (With the exception of 032) are a third gear low rev to redline job.
 
I basically want to look for evidence of knock, because that's what we think it could be.
So basically, if I don't have cf in excess of 6 there is no knock.
I've only ever had a small amount if oil in boost pipes, and thats before catch can.
I'm sure il get to the bottom of it, just got to start eliminating things.
 
I had that kind of sound once on my A6, turned out to be the cat disintegrating, the noice was ceramic parts of it inside the exhaust.
 
thos sounds quite similar to what my car used to and just started again yesterday. when I put my foot down and the Turbo kicks in you get a click click click but quite fast and Loud. What causes it on mine is the engine rocking back causing a pipe to catch on the propshaft. Have a look towards that area. could be similar problem. but everything with my car is a mystery!
 
Block 046

EGT must be greater that 320 degrees

Field 3 must be below 0.50

Field 4 must say B1 ok
 
Thanks finesse most appreciated. Hopefully get round to logging tonight. Will have to wait till the weekend to give the engine a good seeing to. Good thing im not using it recently.
 

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