Pfc Knocking

[eddieeeee-ro]

i've been whoring the search tool on this forum and i still cant work out an answer.

very rarely the engine check light will come on, and when it does the knock sensor on the pfc reads pretty high. last night drove the car on a cruise for like 2.5hrs and knock sensor read 126 once. @ 4600rpm

during the night only saw it ever got to 40 @ one stage.

thing is i havent hear the engine ping inside the cabin.

some of the boys reckon i was shooting flames last night but thats just fuel dumping right when changing gears?

the car tuned @ racepace last year, and recently was retune there last month. b4 and after its pretty much the same, knock goes off rarely.

mods are TB 3" high flow cat, pod, cooler, 12psi, pfc and walbro fuelpump which is only 3 weeks old.

i'm thinking to get some splitfire coils, anyone got any thoughts?

Edited November 17, 2007 by eddieeeee-ro

[moonus]

pinging and knocking are two different things. You appear to have some knock issues. Perhaps take it back to the tuner to have a look at the tune, could be a timing issue due to the onset of heat

[moonus]

if you are not experieicning any pinging, you dont have a plug/coil problem so i woundnt suggest you get splitfires. Knock is really to do with the tune, so your tuner should be able to sort it out for you.

Recieved PM: no probs

[Lazy-Bastard]

pinging and knocking are two different things.

They are the same thing dude

[R33silverS2]

They are the same thing dude

yeh my understanding also

[moonus]

i was of the belief that since he is not experiencing any detonoation, its merely the pfc knock sensor. ie, something to do with the tune? my bad then

[R33silverS2]

i was of the belief that since he is not experiencing any detonoation, its merely the pfc knock sensor. ie, something to do with the tune? my bad then

probably is the tune i.e ignition timing advanced too much.

[Lazy-Bastard]

i was of the belief that since he is not experiencing any detonoation, its merely the pfc knock sensor. ie, something to do with the tune? my bad then

The knock readings on the PFC may or may not be actual engine knock. Sometimes a noise in the engine bay at whatever frequency the knock sensors are set to pick up will set them off. Regardless, the terms "pinging" and "knocking" are both detonation.

[R31Nismoid]

i've been whoring the search tool on this forum and i still cant work out an answer.

very rarely the engine check light will come on, and when it does the knock sensor on the pfc reads pretty high. last night drove the car on a cruise for like 2.5hrs and knock sensor read 126 once. @ 4600rpm

during the night only saw it ever got to 40 @ one stage.

thing is i havent hear the engine ping inside the cabin.

some of the boys reckon i was shooting flames last night but thats just fuel dumping right when changing gears?

the car tuned @ racepace last year, and recently was retune there last month. b4 and after its pretty much the same, knock goes off rarely.

mods are TB 3" high flow cat, pod, cooler, 12psi, pfc and walbro fuelpump which is only 3 weeks old.

i'm thinking to get some splitfire coils, anyone got any thoughts?

Just go back to Benno with that info mate.

If you tell him 4600rpm, what gear and roughly what load, it'll be one cell that needs adjusting and it wont take long

Also your more likely to notice the one cell at night, as the air is colder. Mine was similar ages ago.

Hit about 80 on a super cold night only around 6000rpm in 3rd, one/two cells changed and happy days

[wolverine]

VCT can make a noise around there as an outside possibility which the knock sensor may pick up.

still the best bet its to pull some timing out at that load point.

[DECIM8]

Perhaps unless your not using a aftermarket sensor it could be metalic objects contacting another metal object... see if it happens more so over rough road.

Just an idea cause it can happen quite easily

[eddieeeee-ro]

yeah car will go back for ben to look at.

last night was pretty warm in melbourne tho, wasnt a super cold night.

[NYTSKY]

Ive had my car tuned a few times,as mods were added.My car sometimes shows knock of 80 for a split second at high boost and RPM.

Taken the car back a few times to sort it out.But i was told all is normal.Could be a number of things in the engine bay making noise.

I never hear any pinging but i do get a read of 80 at high loads on occasion.

Tuner is very reputable.And works mostly on Nissans.

[eddieeeee-ro]

yeah, pretty much what my pfc is doing.

[R33silverS2]

could also be fuel, My knock was quite bad on the last tank, cruisin n stuff - was fine. but on wot at about 5000rpm it hit 120 or something. I put in some new fuel and seems to all be good now.

[eddieeeee-ro]

nah mine gets knock on any fuel, did it again 2nite in the same gear and around 4500rpm, so looks like it'll go back on the dyno.

[SilverECR33]

I been having same issue, Due to heat. + more boost. + advanced Timing. from the Manual 120(ish) knock indicates Detonation. In agreement with R21Nizmaid, tuner should be able to fix by adjusting the problem cells.. (which I really gotta get done :S).

[R34GTFOUR]

a power fc reading of 125 is false, if it was correct you would definately hear it even if you didnt know what knock is. The knock sensor has picked something else up and like explained above there are many things that create the "frequency" that the knock sensor is tuned to detect, even rocks/pebbles being flung up into the engine bay can set this off.

If you are driving around with the normal max knock sensor of 40 thats ok. Anything around a true knock reading of 80 or so and knocking or pinging whatever you like to call is audible. You'll know when it pings, its a very distint noise.

To make yourself sleep a bit easier, stick it on the dyno and get a pull done just to double check afr's and knock levels

cheers

[r_palac]

Where abouts exactly do you find these readings??! I own a 34 gtt

[evil_weevil]

Where abouts exactly do you find these readings??! I own a 34 gtt

hand controller on the powerFC