ive got a knock sensor readout on my power fc ecu and it reads up to 100 %. what is acceptable ammount of knock to see ?

 

Does it not read off in bar?

 

well i havnt actually looked myself yet but guy i bought the car off said it reads up to 100 % ? i want to know what to look for tmrw when i take a look at it.

what is acceptable in bar then mate ?

 

No idea on Skylines or anything mate, don't know if its engine specific?

Ones I've seen at my work have had a 3-4bar knock limit

 

Where is the sensor located?
Is it OE sensor?
What frequency is it monitoring?
Calibration?

 

PowerFC knock reading using standard Knock sensors on a Skyline should be set with a warning threshold that when hit will light the management light (depending of course on the mapper)

This limit is usually set to 40 on most cars, but I think it's 60 on Skylines. Anything up to this amount is 'OK'. Spikes beyond this amount may be acceptable too if they really are just spikes and you don't actually 'see' them occur.

 

Incidentally, it's not 100% either. It's just a value.

 

how can you have 100% knock.... its either detting or its not there is no such thing as half a dettination....

you can have pressure values at what the det is at but not a percentage of a det.

 

apparantly it spikes 100 but doesnt hold it il check it today. thanks for the info matey.

 

A 100 spike is pretty high. It's hard to check properly what its doing without actually watching it or using the laptop to log it.

 

would a bottom end starting to fail show as knock on a knock sensor ?

 

yes i would say so

 

I had my Impreza mapped with a Power FC. Up to about 15 was the norm, but occasionally it would spike to 30 or higher. Obviously it picks up interference from time to time too though.

 

I would get it looked at mate :s

 

i can get a low miles late rb26 lump for Ł2800 so i got nothin too loose. im a mechanic by trade so im gonna have a play myself first

 

hits about 30 free revving, but peaked at 101 when i drove it up the road on full boost to 7k.

 

its got just under 2 bar hot idle and just under 3 bar 4k revs above with hot oil.

 

i would spend the money rebuilding youres than buying another...

They are all low miles when they are being sold.

Speak to tweenierob im sure he will help sort it, I always used ron at RK but as rob know the car already he may be better for you.

 

Thought it was only measured from 0-100?

 

i think il ring him monday as he knows the car. i got a friend of mine gonna have a listen tmrw. ive read they have a common fault with the oil pump on the pre 1992 rb26detts. it certainly doesnt sound or feel like a big end failure to me. im gonna go check prices on rebuild parts now if its worst case scenario.

 

i would deffo rebuid rather than buy another....

Im sure ron quoted me a freshen up at 3k...

He also quoted rb30 700hp+ for like 20K+ lol.... Its easy to get carried away with these

 

well ive got a light that seems to flash on when i hear the rattle noise. just found out light is cat overheat light ?

 

It will put in a high peak if you crack the rev limit. That's why you need to see where in the rev-range it's doing it. If it's right at the end of the rev's, don't worry too much, if there wasn't anything too high before that.

 

im gonna get my mate to watch the power fc monitor while i drive it tmrw. what would the garage where you work charge for an engine freshen up mate ? shouldnt be to bad cars only done 55000 miles.

 

Youre gonna be one lucky guy if its just the Cat Knackered....

Good Luck