Knock warning light flickering occassionally (FD with PFC)

[lockwood77]

At Donington on Saturday, I got the cat heat light flickering occassionally (which I understand is the PFC\'s way of warning about knock being too high).

The only times I saw it was once when I was attempting a rev-match from third to second into the chicane (i.e. not WOT and not in gear) and several laps as I feathered the throttle through the Crainer Curves (in third gear and not WOT at all, probably at that point in the throttle where you get some popping). It was very wet before anybody questions my commitment in the Crainer Curves!

Like a fool I forgot to check the knock readings on the Commander while this was happening, but I\'ve never noticed it before on the road or previously at a (dry) trackday at Donington last month.

Rixio was there and said that as long as the light didn\'t stay on (it really did only flicker for a second or less) it\'s probably OK, but I wondered if anyone could enlighten me as to why it might be happening and how to check if it\'s serious or not? :3Confused

Also, am I likely to be able to get the same info revving the car in neutral/stationary as if it was in gear at 80mph+? I don\'t fancy trying to replicate the conditions on the road at the moment!

[probedb]

Mine does this too. it can do it when I\'m in 5th cruising on the motorway and will also do it if I down shift. But it\'s always flickering, it never stays on just like yours!

I\'m off to see Carl in the new year when I get myself sorted and he\'s said he\'ll look at it.

[Eddie]

I may be wrong but I thought this light was to indicate an issue, maybe knock maybe something else, or am i wrong?

My heat light comes on now and again and flickers but when I check my sensor readings on commander mine shows omp sensor problem which is oil metering pump, ok I get knock but nothing major 60 max, unless of course my knock goes up when the oil metering pump is having issues? I use pre mix anyway just in case my omp goes.

Anyone any idea\'s it the heat light is just for knock?

Sorry for posing more questions on your thread.


Cheers

[lockwood77]

No worries Lee, we need to know!

Rixio was saying that knock of 70 or below isn\'t an issue, so I wouldn\'t worry on that score if I were you.

If it is the OMP, it\'s a very useful warning to have (albeit it a worrying one!)

[imebgo]

You can see what is causing the flicker from the the sensors/switch screen on the commander?

Mine used to flicker.. turned out it was was the Cat Thermo Sensor which was all buggered becuase I had my cat removed.

This was shown by the "CAT" and "HWL" blinking on that screen when it flashed on the dashboard.

James

[nikp]

The heat light is used as a warning with the PFC. Not just for knock, but other issues too (like the OMP)

[tezz12345]

my knock is always higher than 60 up to 90 but never on boost only if i rev it hard in first or if it pops n bangs

[tezz12345]

whats omp???

[nikp]

Oil Metering Pump

[Eddie]

OMP is oil metering pump I thought it added oil to the chamber to aid a seal for compression i believe but I am sure some one in the know will tell you for sure.

[lockwood77]

OK, so evidently I need to be looking at the Commander when the light flickers (unless the PFC stores things after the ignition is switched off?)

Are these the sorts of things I\'ll be able to find out without taking the car out and ragging it (i.e. on the driveway in neutral)? Or is it likely that it needs to be under load?

[nikp]

It\'ll only show these things when the fault occurs. For example, the OMP error only on the switch check screen as a highlight over the OMP when it is not working as it should (The OMP is mechanical, but the sensor is electrical)

[lockwood77]

Switch check screen - how do I access that one? Not very au fait with the Commander I\'m afraid! :o

[adib]

:2eek  nock only 90 mine goes as hi as 130 :2Confused

[antrosser]

yeh mine goes to 128! is that a bad sign? lol