Jump to content
SAU Community

Recommended Posts

hi guys,

i did a search & couldnt find what i was looking for - as of yesterday my knock has increased as i noticed this in 3rd gear when i got to 6500rpm @ 24psi, read 70+.

when i reduce the boost level to approx 20psi the knock drops to 40 (as per pfc) & even lower boost showed 25knock.

my tuner will check this out for me but in the meantime i would like to do a check over so i dont waste his time...paul (mr swiper) was suggested i blow out the loom connectors with an air compressor as water may have entered the connectors when i washed the engine bay last week & also to check that the spark plugs all look the same (maybe a plug has failed?)

is there anything else i should check OR has anyone else experienced high knock due to something rattling/loose in the engine bay? i dont want to feel like a d1ck with my tuner if something else is causing this bizarre reading...

thanks.

marko

Link to comment
https://www.sau.com.au/forums/topic/312402-knock-level-increasehmmm/
Share on other sites

  • Replies 66
  • Created
  • Last Reply

Top Posters In This Topic

Possible that you have picked up a bad batch of fuel. If nothing else has changed its weird that it will suddenly change.

I would have it looked at asap.

this is what i 1st thought - i ran the car basically dry then refilled at another bp servo (98 ultimate) & same thing.

It'll probably just be a cell that is slightly in need of attention.

Nothing major

yeah i had a squize at your pfc faq...you are probably right.

i have dropped the boost level anyway, better to be safe than sorry

It'll probably just be a cell that is slightly in need of attention.

Nothing major

+1

Yes indeedy, i had a knock reading of 120 randomly one day doing about 200kph, this was after consistantly never reading over 20 so probs like R31Nismoid said just a cell need a little love :P

Cheers,

Mitch.

or coils if the tune is good

If it were coils I would probably feel the loss in power in higher revs? Although this also crossed my mind

Would a faulty coil cause this symptom, I don't think so as the symptom would be hesitation

I will pull out the plugs tonight and if they look the same then off I go to my tuner

there wouldnt be any loss of power i would think it may just have a little unoticable missfire that would show up as knock. Happened to me.

But to be honest it sounds like your tune as your knock levels went down when you put loss power down.

tuned in summer? temps dropped up there recently? cold night maybe... other than that its probably as Ash suggested if you have already ruled out fuel

It was tuned on a 33deg day, the problem appeared on a 18deg day...could a drop in temp cause it?

Yes, most certainly.

As everyone has said, more than likely just a cell or two that need minor attention.

I think you need to buy a stress ball or something, a minor one-off knock is hardly anything to get excited about. :blush:

Take it back to the tuner, get it fixed. Should take less than 30mins. Drive it sensibly until then... easy as pie!

or coils if the tune is good

u might be right here - ji ust pulled out the plugs & no.4 plug is a lot blacker than the others...when i look at the coil pack for this plug it seems that the black lead tip on it is shorter than the others

paul - you are a legend mate, i think once again u are right - you freak!

i spoke jim @ crd & he explained that the coil pack was mis-firing with the pitted coil pack lead tip which is why the plug was black & this causes all sorts of things i.e. spark over which makes noise, even possible pinging.

i haven't test driven it yet but i'd say it is fixed :D im almost ready to put my head on the chopping block if its not rectified

i will report here once ive take it for a wrap on a long straight, 3rd gear under load

worse case i may need to buy a set of splitfire coilpacks

paul - you are a legend mate, i think once again u are right - you freak!

i spoke jim @ crd & he explained that the coil pack was mis-firing with the pitted coil pack lead tip which is why the plug was black & this causes all sorts of things i.e. spark over which makes noise, even possible pinging.

i haven't test driven it yet but i'd say it is fixed :D im almost ready to put my head on the chopping block if its not rectified

i will report here once ive take it for a wrap on a long straight, 3rd gear under load

worse case i may need to buy a set of splitfire coilpacks

:D

  • 3 weeks later...

hi guys,

last night i took my car for a drive with new my splitfire coil packs & it is still knocking high so ive left a msg for my tuner to look at my car. i was hoping the coil packs would have solved it but anyway...the joy of modded cars!

2nd gear showed 34 peak knock, 3rd gear showed 66 peak knock.

i then cruised below 3krpm in 4th gear @ 60kmh - when i reset the peak knock on my pfc hand controller it immediately shows above 20 peak knock & as high as 25 peak knock (i did this back2back test a no. of times & got the same result every time). HOW is this possible on such low revs??? i think my knock sensors are not reading correctly, either they may might need replacing as ive been told they can fail OR maybe 1 of them has become lose over time, i luv playing the guessing game (reminds me of an ex-girlfriend)

if the problem was just a cell that needs attention as suggested in my above posts, would i still have the same results considering the circumstances i.e. low revs, high knock?

20 on the knock is no issue. Just driving around mine i think sits around 10-20.

There is always going to be some noise picked up, the fuel is combusting after all.

You only really need to worry about knock when it gets over 30-35. Anything below that is largely irrelevant.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Yeah i found that alot of parts can be wrong or "very" hard to get the real right one. I already bought some brakes years ago on me "old" GT calipers and they were wrong too 😄  I told them too. Even send them pictures...but they said "EBC catalogue has them on my car... So i dont know what their answer will be. I call monday them and let them know that they are really not on my car. If they were they would be already on a car...
    • Welcome to Skyline ownership. Yes, it is entirely possible parts websites get things wrong. There's a whole world of inaccuracies out there when it comes to R34 stuff (and probably 33 and 32). Lots of things that are 'just bolt on, entirely interchangable' aren't. Even between S1 and S2 R34's. Yes they have a GTT item supposedly being 296mm. This is incorrect. I would call whoever you got them from and return them and let them know the GTT actually uses 310mm rotors. Depending on where you got them from your experience and success will obviously vary.
    • Hi...a bit a "development" on the brakes. I spoke to the guys where i get brakes from...and they are saying that 296mm EBC are for R34 GT-T. I then went to their site: https://www.ebcbrakes.com/vehicle/uk-row/NISSAN/Skyline (R34)/ and search for my car(R34 GT 1998 - it has GTT brakes) and it show me this USR1229 number and they are rly 296mm rotors... So now iam rly confused... The rotors i have now on the car are 310mm asi shown... So where is the problem? Does the whole EBC got it wrong or my calipers are just...idk know what?  
    • Oh What the hell, I used to get a "are you sure you want to reply, this thread is XX months old" message. Maybe a software update remove that. My bad.
    • This is a recipe for disaster* Note: Disaster is relative. The thing that often gets lost in threads like this is what is considered acceptable poke and compromise between what one person considers 'good' looks and what someone else does. The quoted specs would sit absurdly outside the guards with the spacers mentioned and need  REALLY thin tyres and a LOT of camber AND rolling the guards to fit. Some people love this. Some people consider this a ruined car. One thing is for certain though, rolling the guards is pretty much mandatory for any 'good' fitment (of either variety). It is often the difference between any fitment remotely close to the guards. "Not to mention the rears were like a mm from hitting the coilovers." I have a question though - This spec is VERY close to what I was planning to buy relative to the inboard suspension - I have an offset measuring tool on the way to confirm it. When you say "like a mm" do you mean literally 1mm? Or 2mm? Cause that's enough clearance for me in the rear :p I actually found the more limiting factor ISNT the coilover but the actual suspension arms. Did you take a look at how close those were?
×
×
  • Create New...