M35: How To Disable Awd

[zei20l]

So i need to diagnose a problem with my car so i can FINALLY get it fixed. the dealer is f*cking useless. If i find out what it is, ill get them to fix it.

Ive narrowed it down to a few things, one i tried today (O2 sensor) wasnt the problem.

the 4WD light came on today and the problem didnt appear for the entire journey. so if i can disable the attesa system, i can narrow the problem down and get them to check it out and replace the parts required.

Anyone know how to do this in a non-dangerous way? removing fuse? Craig, i remember you may have done this, can i ask how please?

thanks heaps guys!

[andy65b]

from memory he disconnected the harness at the front wheels, but maybe be a bit neater than his method

What about having a look at the ATESSA computer for any codes, in the back right of the boot behind the pannel.

[zei20l]

is there even a light on it??

there would be a fault logged with the ECU i guess as the screen (and lady) told me about the problem lol

that said, it might be worth replacing or swapping to test. but i think its more mechanical to be honest

[Bis-e Bee]

might be all those burnouts on wet concrete

you have always suspected your gearbox had issues, maybe it's related.

[scotty nm35]

From what ive read, you would need to release the hydraulic pressure to the transfer case to fully disengage the clutch and remove the power to the system but that will throw different codes wont it?

You could try Craigs method, on second thoughts, better leave that to the trained professional.

Whats the problem Iain?

[Jetwreck]

What s the exact problem....is it just the 4WD light coming on? If so one of the other guy suggested to put the car into drive - foot on brake - stall it up.....4WD light should not come on then.

My method (lol.....I'll hold back on the whole scenario). Unplug the sensor in the front right hand guard.....grey plug....this will make you lose ABS and the 4WD sensor.....therefore the 4WD will not know what to do......should only give power to the rear even after wheel spin starts(well it did with mine).

any other ?'s you have my number

Edited February 18, 2010 by Jetwreck

[zei20l]

im getting a shudder at around 40km and sometimes higher speeds. always low rpm (its not a misfire) as in 1500rpm and lower and always on a flat surface. if i can disable the 4wd system and it goes away, then that will at least point me in the right direction.

it was first thought to be gearbox (and still might be) as it only seems to do it when its in 4th and 5th and OD/lockup has kicked in. we were thinking it was the lockup solenoid or the clutch pack (i cant remember what its called) that controls the overdrive that can apparently cause shudder.

anyway, yesterday when the 4WD light was on, it didnt do it the entire journey!

i tried cleaning the plugs down under the car also with some contact cleaner. didnt appear to help at all.

[zei20l]

ohh craig, that sensor, its just 1 plug in the wheel arch?? is that just the ABS sensor for that wheel? i guess not getting one signal the car will shit itself and disable all the systems. i like

[Jetwreck]

sounds like a similar shudder to mine.....I get it through the front when I am under even the slightest power with a slight lock on.... turning left or right. However I don't remember it doing it when it was 2WD.

[zei20l]

hmm ive never tried on full lock!

however, ive heard at low speeds at full lock with synchro mode on, the car will brake the inside front wheel to help it turn a little sharper.

im gonna test this over the weekend. the plug is easy to get to?

[iamhe77]

sounds like a similar shudder to mine.....I get it through the front when I am under even the slightest power with a slight lock on.... turning left or right. However I don't remember it doing it when it was 2WD.

You mean like if you have a left or right lock (or close to) when backing into a car space slowly?

[zei20l]

nah i get that too, its the AWD locking the wheels. i notice when i have sync mode on that the turning circle is shit and the car needs more throttle to get it going.

[Jetwreck]

If I gun my car in a straight line I get now vibration....If I gun is with a slight(very slight) left or right lock I get a vibration.....even after I have straightened up.

[zei20l]

might be the CV/uni joint in the front drive shaft. maybe remove it and try again.

ive been searching and R32/33 and C34 people have had some vibration problems similar to yours mate!

check if they are loose

[pixel8r]

(re: zei20l) If I understand your problem correctly - its when you're cruising at anything say below 60km/h and the torque converter lockup occurs - it will do a single shudder as the torque converter locks. Is this correct? just the one shudder...well, one shudder each time it locks/unlocks...

I was always under the impression that the torque converter should only lock when you're going faster than 80km/h, but in these cars it seems like it can happen at almost any speed provided you are at fairly constant throttle and the revs are high enough not to stall once locked...

It also will lock up from either 4th or 5th gear, hence the ability to do it at such low speeds.

I always thought this shudder was normal - just a side effect of the torque converter lockup happening. Its a bit annoying because for me at say 40km/h its only revving slightly above 1000rpm and most of the time it is continually locking and unlocking every time my foot touches the throttle or moves .1 of a mm.

If I had to guess, I'd say that this behaviour is normal and that if it detects a problem with awd it maybe doesn't do the torque converter lockup at all? Disclaimer: This is just a wild random guess without any in-depth knowledge of the system at all.

[iamhe77]

Shouldn't get a shudder when the torque converter locks/unlocks

[zei20l]

no my shudder is constant, and i can make it occurr for probably 10 seconds, and it gets worse the longer is goes.

ive driven enough autos to know when lockup occurrs, but its not harsh like im getting.

maybe, just MAYBE, the lockup IS the problem. i can be cruising at 100km/h, i might squeeze my foot to go up a hill and it will release and the revs go up. normal im guessing? (lets assume im in D and not M) sometimes, i can be in the same situation, and it wont unlock, and i REALLY need to push the throttle for it to kickback to 4th to overtake etc.

its weird, but disabling will at least take the attesa out of the picture. assuming it continues to do it while its disabled.

i should also look at WD40ing the throttle input attached to the pedal. it might be worn or dirty down at the bottom end where its driven most

[andy65b]

i should also look at WD40ing the throttle input attached to the pedal. it might be worn or dirty down at the bottom end where its driven most

Use circuit board cleaner rather than the WD40. If you need some pop round and you can use mine.

[zei20l]

i have that also. good idea

[scotty nm35]

Quite often I get a shudder, mainly when at full throttle. It feels like gravel in the gearbox but it only happens when the power transfers to the front. I assume it is the clutches slipping in the transfer box as its not meant to handle the torque im throwing at it. Perhaps your clutches are worn?

It could also be some sort of traction control, that's what it feels like...