R34 Losing Power

[kyle345]

Ok to keep it simple as possible with no confusion

I own a R34GT Auto

For some reason when i press the accelerator the car feels heavy like its struggling to get power, the revs dont go up in sync with when i press the pedal, almost goes to the floor before power kicks in but its still very week.

Sometimes it runs fine and this doesnt happen so this tells me its an electrical problem seeing as its intermittent. It seems to only happen on cold starts, and if i start my car hot it seems to be fine sometimes. The performance does not change during driving you have to physically turn the car off and back on.

Ran scan tool and i got these codes.

Engine: P0325 Knock Sensor - B1

A/T: Shift S/V A(P SW)


I doubt its the knock sensor so i think its to do with the transmission code but have no idea what that is.

Car has done 160,000km


Any Ideas????? Cheers

[GTSBoy]

Take it to a mechanic. Pay money. Get it fixed.

[ichi-go]

Ran scan code and it says knock sensor but you "doubt" the scan code?

What would your strong analytical skills suggest then?

[kyle345]

I am a mechanic... A knock sensor is not something that would cause power loss.

My theory it is something with the gear box like it is stuck in limp mode or something so maybe the shift solenoid needs replacing. So im thinking thats what shift s/v stands for. "Shift solenoid valve".

Could be wrong im just not sure because this problem does not throw any lights

[kyle345]

Knock sensor could be the reason its become so sluggish though

[Ben C34]

Knock sensor won't make it sluggish but could cause power loss? Wha?

[GTSBoy]

Code refers to a shift servo valve that appears to be related to the power switch. Shouldn't make it run crook on its own. Suspect the tranny might be on its way out in general.

[Chris32]

Dud AFM or CAS?

[asps91]

knock sensor could be throwing it into limp mode right?

[Ben C34]

knock sensor could be throwing it into limp mode right?

Maybe.

I don't think it would go into a limp mode as such (doesn't exist) , but would likely be running on the knock maps which are rich and have timing pulled.

And your trans is unhappy.

[asps91]

thats exactly what was happening on my overboosting mr2 a few years back. I kept blowing knock sensors.

[Ben C34]

Wtf . Blowing knock sensor.....

And this isn't an mr2

Edited March 25, 2014 by superben

[asps91]

The knock sensor is very delicate on the 3sgte and there have been many counts of them failing once they take a high reading of knock for your information.

Im obviously aware that it is not an mr2, i am just imputing a real world experience i have gone through with simular symptoms. No need to be rude about it mate... We are all here to help after all.

Edited March 25, 2014 by asps91

[kyle345]

Hmm doubt its CAS or AFM. Because its not throwing a primary ign code.

I wonder why its only sluggish when it starts cold but if i start it hot its heaps better.

Thinking about giving it an AT service and replace that solenoid because i know thats the reason why sometimes AT light comes on and gets stuck in 3rd (common problem after they reach 140,000)

But sluggish wise i dont think its the AT

[kyle345]

Any ideas?

[Ben C34]

Yes. The f**king knock sensor and the fact your trans is unhappy can't be helping.

Fix the error codes on ecu. That's why they are there.

What do you want to hear?

What do you want to fix?

Also cas or afm won't cause an ignition error code. Problems with the coil packs or coil loom will (that is the ignition system)

Edited March 26, 2014 by superben

[kyle345]

Research primary ign code for r34 - can be CAS AFM or coil packs.

And im saying what if this is the torque converter and not to do with the codes

[Ben C34]

21 is ignition code.

What have you seen that says the cas and afm don't have an individual specific code for them? Cos they have their own codes.

Maybe your research isn't up to scratch?

www.skylinesaustralia.com/forums/uploads/post-50241-1260308643.jpg

anyway,do what you want. Ignore the knock sensor code, worry about the converter etc....

[Ben C34]

The description for code 21 is misleading. It will occur when the coils or loom has a fault that the ecu detects it.

[kyle345]

I dont know if it was 21 but i had the code before when my car wouldnt start 'primary ign' it was the CAS overheating, pour cold water on it and it starts again