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I have recently tuned the RB26 engine in my stagea which is producing just over 500bhp with decent torque on low boost setting (506 at flywheel on a 4wd dyno )

The car drives fine on low boost including full right foot. The problem is do the same on high boost and the only the rear wheels spin . This is including on the dyno (although it may not have been tied down that well )

This is quite annoying as high boost is rendered close to useless.

The car has manual gearbox and Goodyear F1s tyres (245 40 18) all round. All the plates in the transfer box have been changed. It has an F con V pro ecu and I have just fitted a gilken twin plate clutch as the old one would not take the power.

Previously it was possible to get all 4 to spin in 1st now just the rears do this. This was only in very low gears and when being "silly"

The abs light is permanently on and so is the 50/50 split light although the latter has always been on since I got the car (2 years ago) which is way before the problem ever appeared .

My question

Could this be a problem with the ABS sensors/wiring the ATTESSA ecu or g sensor or do I just need larger/stickier tyres

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Have a search on this site (or Google) for the Atessa and ABS error codes (and how to generate them). The fact that the abs light is staying on suggests a problem you have always had but has only now been highlighted by the extra power you have now.

thanks for the help so far.

To confirm

In fact it is the 4wd light that comes on not the syncro light. This has always been on. the transfer box has been rebuilt and it made no different to the light.

The abs light has only recently come on.

I will try to get an error code.

Sounds like a wheel speed sensor failure, as the ABS and attessa use the same sensors i believe? unfortunatly to get the fault codes for the attessa ecu means u have to pull the LH rear trim all out to be able to see it. I cut a small hole in the pocekt on the LH side of mine so i could see the LED fault light once the car is all back together.

Checking this light will be the first thing id check.

Ok

have found the ecu.

At the moment it does the following when the ignition is turned on

flashes seven times slowly

then flashes five - two - four - three times all quickly.

Then repeats 75243 etc

Any ideas greatly appreciated

in the meantime you might want to look at some whiteline subframe bushes

basically you can change the orientation of the diff to give you more traction

this wont fix the root of the problem but its a good idea to do regardless

only about $110 or so

Bled the attesa fluid?

will be trying this in the next few days just wondered if anyone knew the error codes .

Re bushes. Done some and arbs - I can order anything through whiteline as I have an account with them but the problem is stock levels in the uk ( have been waiting 2 months for one order)

I was going to do the rest of the bushes and fit adjustable arms soon any way but this came up so need to do this first.

some progress ?

Have bled the attessa system and changed fluid at the same time as had not been done since the car came to the uk. A few bubbles but nothing obvious .

No change

Now I am fortunate in as much as I have a few other Stageas about so swopped the "easy to change parts first"

Changed the awd and abs fuses and relay

No change

Also swopped attessa ecu with another with the same part no.

This gave the same error code immeadiately as the original ecu

7 slow 5 2 4 3

will try diagnostic mode next....................unless of course anybody has a better suggestion

id be lookin at attessa system as well, its definately not too much power i had alot more and only spins 1st gear and a touch of 2nd in 4wd with street tyres (11.3 @ 124mph at drags on 235/17 street tyres). Was the clutch packs replaced since the 4wd was right and now its not or did they get replaced and 4wd was fine and then suddenly started playing up?

id be lookin at attessa system as well, its definately not too much power i had alot more and only spins 1st gear and a touch of 2nd in 4wd with street tyres (11.3 @ 124mph at drags on 235/17 street tyres). Was the clutch packs replaced since the 4wd was right and now its not or did they get replaced and 4wd was fine and then suddenly started playing up?

All the work was done at the same time when the engine was out this included the ecu change (f con from power Fc ) rebuilt forged engine ,clutch,transfer box etc

Before the work power was 415 bhp with about 350 ft lbs of torque

The spinning problem has only become noticeable since the engine work but I dont think it was there before because even though the 4wd light was on it would spin all four wheels (only ever in first gear and never just the rears)

now only the rears ever spin

As the car was run in any problem was not noticed straight away.

The abs light has come on quite recently and this was definately after the spinning was noticed.

.

This may be a stupid question as I am not overly familiar with the C34, but could the drive shaft have been "dropped" for a dyno run?

I know with earlier Skyline's that you could pull a fuse to get it to run in RWD, so could the tuner have done something along these lines to get a slightly higher dyno figure and not re-instated the AWD properly?

This may be a stupid question as I am not overly familiar with the C34, but could the drive shaft have been "dropped" for a dyno run?

I know with earlier Skyline's that you could pull a fuse to get it to run in RWD, so could the tuner have done something along these lines to get a slightly higher dyno figure and not re-instated the AWD properly?

Not a stupid question at all.

But its not happened for sure . I was there for the recent dyno test and it was a 4wd one .

Also the power has been confirmed within 10 bhp on another 4wd dyno when it was origonally mapped by the guy who built the engine ( was 515)

Re looking at the fault codes

7 5 2 43 as far as I undersatnd gives 43 which is supposed to be - ABS actuator motor , motor relay and circuit

Ive changed the 4wd relay already so will try to find the ABS one and then its looking for a dodgy connection first as thats more likely (IMO) than the motor (I Hope ! )

Well after a day and a half of taking the car apart the problem has been solved. :)

Swopped every relay even remotely to do with the abs or attessa using the spare Stagea. Still the lights on.

Last thing check the G sensor. Suddenly it all makes sense.

The sensor is showing red not white but more importantly its not in the normal place.

The car has been converted to a maunal with RB26 in japan so has a different center console which has a small opening compartment just behind the gear lever.

With this in place the g sensor cant be mounted in the normal postion so it had been wedged in place about four inches further back. Over time it had worked itself loose and was effectively moving about with the car - not good for a g sensor.

I have removed the compartment and refitted a new sensor in the correct position so that it is bolted to the body as normal and does not move. Will have to make a cover for the hole but no problem as a retrim was planned for the consul anyway.

The ecu lights not on and the wheels dont spin........................................unless of course I use the launch control.

Thanks for everyones help

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