interesting problem...

[justinc]

Had an interesting one this week.

Td5 D2, had a turbo failure (Big time, engine runaway the whole deal, was able to stall it out though luckily. Would've been a total loss if it was auto:eek:)and was towed in.
After turbo was replaced, and a chipped ECU was fitted, (NOT a Tombie one unfortunately, it was an early non flash model:() it still had average performance. I checked ECU, AFM, replaced fuel pump as it was 200+k old, checked and adjusted valve timing and injector bump clearances and ran diagnostics in realtime while driving. Still no clues. :mad:

It was then I noticed the ECU was being told the vehicle was in Low range. When I selected High, the ECU was told Low, and vice a versa.

After unplugging and bridging the connector on the TF case, it was a goer. A real goer.:twisted:

I am ata loss to explain why this happened. Apparently the vehicle has never had good performance, even when new. The upgraded ECU made it worse as the mapping for low range is really 'flat' to make good off road driveability.

Anyone have any ideas as to why it happened?

And Tombie, WHEN ARE YOU GOING TO MAKE NON FLASH ECU'S AVAILABLE????


JC

[scarry]

I wish i could do this to my sons commodore.....it might slow him down:D:p;)

[LandyAndy]

Thanks JC
Something else to look into with mine.
Sometimes its a flyer other times a gutless slug.
Need to do more work with the Nanocom and Laptop.
Andrew

[Psimpson7]

Wiring fault from new maybe?

dodgy repair early in its life?

[Tombie]

Nope!

Factory fix for surging issues in some vehicles....

They inverted the mapping in the ECUs to remove throttle sensitivity in High by flipping the internal settings....

Mines like that.... (Hard chipped ECUs only)

[Shaker]

Nope!

Factory fix for surging issues in some vehicles....

They inverted the mapping in the ECUs to remove throttle sensitivity in High by flipping the internal settings....

Mines like that.... (Hard chipped ECUs only)

How do you find out if it has been "flipped'?
Also is it hard to reverse?
Mine is like LandyAndy's .... a gutless slug.

[Tombie]

How do you find out if it has been "flipped'?
Also is it hard to reverse?
Mine is like LandyAndy's .... a gutless slug.

Impossible to "flip" without fitting a different chip.

Gutless isnt that issue commonly, mine was going hard as is.

I have a fuel pressure issue killing my power at the moment.

[jmkoffice]

Thanks JC
Something else to look into with mine.
Sometimes its a flyer other times a gutless slug.
Need to do more work with the Nanocom and Laptop.
Andrew

Andrew, interesting!

Mine performs well normally, however after towing the caravan 500+ km, it drives like a bloody rocket when the caravan is removed (no not imagining it). It's almost like the ECM has configured itself to be more responsive or something? After driving for a while it reverts back to "normal" performance again.

Has anyone else found this?

[justinc]

Had an auto one today (2000MY) and it is also configured that way. Apparently the standard mapping isn't as critical with auto ones as they arent effected much in low range IE no clutch/surging issues etc.

JC

[Blknight.aus]

FWIW from memory the switch is open in one position and closed in another... I think that there is a couple of aftermarket switches that will fit in the switches position but the NO/NC of the switch is reversed... might be worth mulitmetering the switch....

[justinc]

FWIW from memory the switch is open in one position and closed in another... I think that there is a couple of aftermarket switches that will fit in the switches position but the NO/NC of the switch is reversed... might be worth mulitmetering the switch....

Dave, switch on transd works fine, IE it no longer allows hill descent etc since being disconnected and bridged. It looks like Leo109 has devised a secret and most cunning circuit to flip the signal (post SLABS ECU) so the engine ECU gets the correct signal, but the Slabs /ABS/HDC gets the right one too.
I'll keep you informed:)
JC

[LandyAndy]

Hi JMK
Towing the caravan would give the engine a great workout removing any varnishes or glazing form the bore.It will improve horsepower so its not your imagination.
Andrew

[Leo109]

Nope!

Factory fix for surging issues in some vehicles....

They inverted the mapping in the ECUs to remove throttle sensitivity in High by flipping the internal settings....

Mines like that.... (Hard chipped ECUs only)
Hi Tombie As Well,

So, does this mean these vehicles are extra, extra touchy in LO? Seems an odd 'fix'.

And from your later reply, it seems this inversion of the HI/LO switch input is hard-coded into the ECU - and it doesn't even get 'restored' to normal when the chip is upgraded? (like the BD upgrade JC had done on the vehicle in question).

It seems the SLABS/ABS read the state of the HI/LO switch 'normally', so only the input to the ECU needs to be 're-inverted'. Think I've sussed out how to do this quite simply. Do you happen to know if the HI/LO sw. is definitely a 12V circuit, do you? That is, it's not a reduced voltage (e.g. 8V or 5V) circuit for some obscure reason, is it? (I can measure one next week at JC's but it would be handy to know this weekend if possible.)

Thanks,
Ian

[Leo109]

The little add-on circuit did the job on this vehicle. Inserted into the loom just before the multipin plug & socket adjacent to the main ECU in the RHF corner of the engine bay.

It "re-inverts" the HI/LO signal to the engine ECU so that it reads the switch position in reverse but, as a result, uses the correct map in HI & LO. At the same time the SLABS ECU still 'sees' the switch position correctly and so, Hill Descent etc. still works properly.

Still confused as to how they'd do it and why the factory would consider this a 'fix', if it resulted in really lousy, super-touchy throttle response in LO. Any clues Tombie?

Ian

[Tombie]

Gday Leo

No idea why they decided it was a fix, when a simple remap could have fixed it...

However, I dont know why BD never sorted this on their chipped versions.

I dont do hard wired chips currently so have not seen if I can reverse this.