Hunting Idle Whilst Driving - R33 Gtst

[tigr33]

hi all,

been having some problems with me r33 gtst. On idle it wont hunt at all (revs stay about 1000rpm tho), but as im driving and put it into neutral to come to an intersection it starts bouncing between 400-1500rpm (sometimes stalling), it only does this after its had load applied to it. I've tried to search and found a thread or two but i did the things they said to do, but nothing helped,I've tried:

- spark plugs, all good, gapped at 0.8mm

- acc valve, was dirty and cleaned it out

- throttle body cleaned out

- spray contact cleaner on most connections

- borrow some1 elses afm, no difference

- checked for weird noises but nothing

- checked all hoses and pipes, for vacc leaks

- checked charcoal canister

- cleaned out BOV

- regrounded fuel pump (inside the boot)

mods on my car are:

Garrett gt2535, stock ecu with SAFC, full exhaust, blitz pod, cooler, turbotech b.c, sard FPR, catch can

got the car dynod at pretty much 200rwkw (which i thought it would be higher) and tuner couldn't find the problem as he ran out of time to find it.

could any1 with a similar problem help me out?? or even throw ideas at me so i can check it

also i might have forgotten some things i've tried so if i remember, i'll do an edit

Edited April 7, 2007 by tigr33

[HKS99]

using a powerfc? or atmo bov?

[Gazee]

take it back to him it needs to be more finely tuned with the dec. air thingo on the safc... your cars acting like its got a atmo bov on it.. stalling n shit or its blocked off and its stalling cos the turbo is generating more air and pressure and its over fueling.

[tigr33]

finely tuned with the dec. air thingo on the safc.

he's a pretty good tuner, im sure he would have picked up on it tho, what is this ur talking bout/ or do?

also has stock bov

Edited April 4, 2007 by tigr33

[J34]

I just had a similar problem and it was just a simple adjustment on my Power FC. Get you tuner to check your SAFC as it may only be something simple. :sorcerer:

[tigr33]

yer i will, but the only thing was that this problem started happening a few weeks after i got it tuned, it didnt happen straight away as i drove out, thats y im looking at other things rather than the safc..

do u remember what had to be adjusted on the safc??

[Devils_Advocate21]

Coils? and plus if its been tuned how rich is the tune as well?

[The Dan]

Air leak. Same issue on another R33 and it was the charcoal canister leaking. When it's doing it you can get a pair of pliers and block the vac line that goes to the canister. If the idle settles then there is your problem. After you have found your issue, you can sit back and have a beer, look at what you have achieved and be glad with yourself. Or not.

Problem might not be canister but I'm betting air leak somewhere......the tuning suggestion is not likely but still can happen.

[tigr33]

Coils? and plus if its been tuned how rich is the tune as well?

havnt had probs with the coils at all, they were cleaned out with the dremel and siliconed over a year ago and never had dramas, unsure on how rich the tune is too, i'll suss out the coil tomorrow tho

Same issue on another R33 and it was the charcoal canister leaking

i'll give that a go as well tomorrow

thanks heaps guys, keep these ideas coming in i'll go as many parts as i need to

Edited April 5, 2007 by tigr33

[Devils_Advocate21]

in regards to the air leak theory that happened to me and was a leaking vac line been too loose (charcoal canister) thats another thing as well to consider 1 point zip ties are your friend on that issue it helped me, but i had an issue as well with my tune which is now thankfully sorted thank god. but a major on this issue is air leak somewhere. Good luck with it all

[esky_mad]

maybe take off your acc valve and give it a clean, seems alot of 33 owners find it fixs a few idling/hunting problems

[esky_mad]

haha sorry dude you spelt it wrong+im blind good luck:cheers:

[BAMR33]

AFM needs cleaning

[siddr20]

^ hes cleaned the aac value and even changed afms..

i cleaned my afm, and it didnt help at all..

For my 100k service, i got a enviro service done, which basically cleans injectors, throtle body, fuel lines etc etc.. With carby stuff..

That helped my idle issues by 75%.. Actually for the first two weeks the idle was perfect!! then after that, it only does it sometimes (on a really hot day ie. hunts around 500-700 at most)

Maybe give that a go.. Plus it will make you car healthy and its good to clean out all the crap that comes out of your engine!! esp if the car is ike 10 years old

Otherwise go back to the tuner, and see if he can fine tune the safc once aagin..

gdluck n let us know what happens..

[tigr33]

AFM needs cleaning

already wrote that at my 1st post, and changed it.

siddr20: i'll have a look into this, i got injector cleaner at home so i might slap that into the tank 2day

damn rb25's, there too hard to work out problems like this, any1 else with an idea?

[Green_s13]

really simple on but have you check the timing on your car i had issues with my car hunting and the timing was out by about 4 degrees, set it back to what where it should be and the hunting went away

[Dobz]

like others have already said it sounds like the engine is fuelling up too much

i'm guessing the higher you rev the engine then let it drop bak to idle the further it dips below idle speed and hunts up and down, it most likely stalls when the engine is cold. correct?

best get the tuner back onto it

[tigr33]

yep dobz that exactly wot its doing, i've pretty much narrowed it down to the tune &/or timing now as well. i grounded the feul pump right after it comes out into the boot (read this on a thread last night) and cleaned out my stock BOV, and no difference

i will go see the tuner this tuesday, also i put a metal intake on a few weeks ago (ditched the old rubber one) , i cant c that being a prob tho, is it?

Edited April 7, 2007 by tigr33

[Dobz]

nah the intake wouldn't affect it.

just a question is the stock bov plumbed back into the intake with the new pipe?

[tigr33]

just a question is the stock bov plumbed back into the intake with the new pipe?

no, the stock pipes are used, just cut slightly shorter so i could fit hose over both pipes to join it onto the intake, i've checked the connection and the hose was a tight fit so it wouldnt be leaking