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that muh power issues were caused by the knock sensors, some new ones went in on friday last week and the car has been running awesome, there is power like right there if that makes sense.

basically whats happened is, when the knock sensor(s) are malfunctioning, they are thinking that there is detonation in the engine (when there might not b any...it just might be vibration).........anyways when this happens, it retards the timing........therefore less power :P

the thing is the ecu doesnt recognise that the knock sensors are malfunctioning.

anyways she is going on the dyno fri arvo :D will let you guys know what happens

hopefully no one will hijack my thread this time round but im not counting muh chickens before they hatch.

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that muh power issues were caused by the knock sensors, some new ones went in on friday last week and the car has been running awesome, there is power like right there if that makes sense.

basically whats happened is, when the knock sensor(s) are malfunctioning, they are thinking that there is detonation in the engine (when there might not b any...it just might be vibration).........anyways when this happens, it retards the timing........therefore less power :D

the thing is the ecu doesnt recognise that the knock sensors are malfunctioning.

anyways she is going on the dyno fri arvo :( will let you guys know what happens

hopefully no one will hijack my thread this time round but im not counting muh chickens before they hatch.

Are you going to use genuine knock sensors? How much do they go for? I might consider changing mine as my car sometimes pings even though I use 98 RON. (stock RB25 NEO - Non-turbo)

Cheers

i got some second hand ones from a wrecker - r33 gtst knock sensors fit perfectly into the r34.

i picked mine up for $35 each

iseekool: maybe get some one to have a look at your timing, maybe it has to be put back a bit

lol. iseekool: Faulty sensors or not - knock is knock = tuning problem! Cara and her mechanic probably weren't even able to hear any knocking because the sensors were giving false positives. Good stuff cara, glad you're rolling well again! :D

Edited by sl33py

You've got a Power FC right? They don't have knock control, and don't scale maps based on knock signal. All they do is read knock and display via the engine light.

So wouldn't have thought the knock sensors would do anything????? May still be something underlying that's intermittent.

Edited by ChillehExtremist

if the sensors are faulty and are always thinking there is detonation in the engine.........then like i said before its just gona keep the timing retarded instead of letting it be as per normal.

and yeah i got a power fc, but even on a stock ecu, it wont pick up if there is a malfunction with the knock sensors.

i guess its just one of those weird and wacky things that you just learn along the way..........ive had 4 mechanics that i know of say the same thing when ive told them what happened "yeah....that makes sense" lol

and what do u mean by display of the engine light? just cause there is detonation dosent mean the engine light is gonna come on.......

only of recent if the knock is over 60 has the engine light gone off and then back on again(due to the power fc being for a gtt it thinks there is a vacuum line missing when its not)...my safe level of knock is anything below 60........anything above, well she has to be put on the dyno pronto to see whats causing it.

power FC will not regard timing with knock of 10, 20, 60 or even 100. only the standard ECU will retard timing based on feedback from the knock sensors (and of course sometimes when they are faulty the stock ecu will retard timing even though there is no actual knock).

again, power FC will NOT retard timing due to knock (real or faulty).

What Baron said, the power FC just doesn't have that function/capability. I'd still be looking elsewhere for the fault.

The check engine light flashes when it detects a pre-determined knock level (say 50) that's how the power FC works. It won't show a constant check light, as that indicates a sensor failure.

hey cara, did the pfc connect straight up & everything worked as normal? yup sure did

did u have to get it tuned to suit the NA ? yup

ne real gains from the tune on the pfc? yeah cant remeber what atm tho lol she was doing i think 120 then went up to 128kw

how much power is your car putting out now without nos. - dunno find out friday :D

hey everyone

havent been able to do the dyno run yet.......... :) have had to work endlessly atm and i need to change the oil aswell cause she has decided to chuck the shits on the pennzoil we put in just before Autosalon.....the oil is black as and that was after 4 weeks! so im putting in my Nulon Fully Synthetic again aswell as putting in a flush to get anycrap out.

will let you all know

im also waiting to hear back about some possible exciting news that could be happening.............

its enough to get any turbo owners nose out of joint! :):D

128 kW with Power FC.

i wont say that pennzoil is a shitty oil, but ive noticed a pattern with the car, it just dosent like running on normal oil, but chuck in fully sythetic and she is happy as. its weird,

Mineral oils will always discolour more that semi or syn....change in colour isn't a bad thing, change in viscosity is a definite sign of break-down though.

What oil temps are you seeing? Normally 130+ would see that happening so quickly, if the temps are OK it's purely how the oil behaves.

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