knock link

[A80Avant]

please do!
i just ordered the knocksense!
i hope it can be made to work properly!

[EspenW]

Cool, having done a little further reading, it seems that the KnockLite has some issues with the sensitivity as well.

[A80Avant]

isnt the 3cylinder the one that gets all the heat on the 5cyl engines?maybe a screw in the vicinity of that would be good,what do you say?

[EspenW]

I was thinking about the same, the knock sensor should definitely be mounted as close to the hottest cylinder. Question is which one is it?
I looked around, and found a few threaded holes on the block that would be suitable for a knock sensor, but access with a torque wrench is limited (gotta pull the radiator, etc). It is highly important that knock sensors are torqued to exact spec.
Would also be a good idea to clean the threads with a tap, to make sure that the torque reads correct.
I will have a look from the underside of the block tonight, to see if access is better from there.

[A80Avant]

perfect! keep me posted.my knocksense is in the post!

[S2central.net]

Oh this is related to Espen's other thread - cool. The Bosch knock sensors are a two-pin device on the S2/RS2 engines. There is a 3rd wire used as signal screen that is earthed IIRC. That is pin 3 on the sensor connector... You should be able to use pins 1&2 as the source of the knock signal - that is all the ECU connects to.

You lucky boy with 99RON and E85 to play with - I'd have thought knock is the least of your worries (except when dabbling with tuning parameters as you seem to be doing).

PAul

[A80Avant]

i got an extra sensor to mount somewhere as i dont want to interfere with the OEM sensors....i hope i can find a decent place and also have a good reading!

[EspenW]

Yep, 99RON is nice for the RS2, but not even close to good enough for the Golf.
Remember that the Mk1/Mk2 Golfs with 10:1 can pink on 98 octane, and I'm running 11:1 (w/a 2L Audi ABK bottom end).
Knocks bad, even at 6BTDC (which actually gives most power too, have the graphs to prove it..). On E85 on the other hand, not even the slightest sign of pinking.
IN the RS2, I'm really not that worried about knock, since it is mapped for 1.8bar using 98 octane, and I'm feeding it 99 Octane. However, it is always good to have some visual confirmation of what the ECU might be doing, in case of a bad tank of fuel, clogged injectors, etc.
The Knocklite input hooks up to only the knock signal wire going into the ECU (in addition to rpm and system 12v/ground, of course.

[A80Avant]

espen,
when you will hook it up and calibrate the frequency give some input as well,to make the same calibration.Boris told me that it will be set to 7000Hz which thinks is the correct frequency but you never know!

[EspenW]

Frequency is set at the factory, but sensitivity is adjustable (on both the Knocksense and Knocklite).
The way that I set up the Knocksense in the Golf was by revving to redline in neutral, adjusting the sensitivity so that it would not trip the light.
The Knocklite will have a similar adjustment, but engine noise at idle, mid rpm and max rpm are programmed first, so that the unit knows what the engine sounds like, making it easier to differentiate knock from engine noise.

[A80Avant]

oh i see!

[EspenW]

I deleted the aux rad and replaced the plastic coolant flange on the rear last night, so I had the belly pan off, and had a look at the block from below.
Found that there is a threaded hole on the exhaust side of the block, but you need to remove the AC compressor in order to get access with a torque wrench.
Another option is to get a longer bolt, and place the new knock sensor right on top of the factory one for cylinders 4 & 5. The sensitivity of your standalone sensor will go down, but that should not be a problem, just increase the sensitivity of the Knocksense box. Not sure if it will afffect the sensitivity of the factory sensor. It was Boris who suggested this when I installed the Knocksense in my Golf. This location is easy to reach with your torque wrench.
I checked out the wiring going into the ECU, and splicing into the signal wire going to pin 11 (signal from Knock sensor I) should be easy. Carefully remove the insulation of the wire, a little soldering and heat shrink, and thats it. I'm going to do this.
That way I see the same signal that the ECU does. Knocksense/Knocklite are high impedance devices that will not affect the signal going to the ECU.

[EspenW]

PapVas: did you install the KnockSense yet?
I just got the Knocklite (along with piles of other goodies from the US). Will install this week

[A80Avant]

i have postponed the installation of the knocklink because for now i dont think it will be needed.Probably i will install it on my next upgrade or so.

[EspenW]

Hmm.. considering the fuel quality and hot summer temps in Greece, I would install it.
Easy to install.