ECU repairs

Stempy · Unread post by **Stempy** » 05 Jul 2009, 21:04

I think it's quite unlikely as it's the suspension ECU I'm working on at present

Sid_the_Squid · Unread post by **Sid_the_Squid** » 05 Jul 2009, 21:12

rofl..
thought it was the gearbox one...

DickieG · Unread post by **DickieG** » 05 Jul 2009, 21:31

I have the distinct feeling that hoping to find a fix for the occasional coarse gear change on an automatic gearbox in a car the age of a Xantia is akin to looking for the end of a rainbow. I drive quite a variety of automatic high end car's at work and even they still snatch some changes as described in earlier posts, the auto box on BMW 5 series circa 2002 can change with a real clunk and even some of the very latest BMW 5 series and Audi A6 suffer from it.

Sid_the_Squid · Unread post by **Sid_the_Squid** » 05 Jul 2009, 21:43

Interesting stuff DickieG.
I can’t speak for the other V6ers, but certainly my main concern stems from a paranoia about my box dying, even the slightest irregularity and I'm thinking apocalypse. Its comforting to know that it’s a quite a normal quirk.

Stempy · Unread post by **Stempy** » 05 Jul 2009, 21:55

I fear you could be very right Richard, especially considering that they all seem to do it. Maybe someone with an intimate knowledge of ECU source code could modify the programme and then we could all upload it via the Lexia.

In fact it's entirely possible to modify your driving style to virtually eliminate it happening. But at the end of the day, anyone using this forum is the type of person who just can't resist a good fiddle, and if you knew some of the things I have fiddled with on my Xantia you'd probably think I had nothing better to do.

Sometimes I wonder myself, but I guess it comes from my biking days, where every last bit had to be changed in some way to make it better (or sometimes not) than the next blokes.

Sid_the_Squid · Unread post by **Sid_the_Squid** » 05 Jul 2009, 22:06

Maybe someone with an intimate knowledge of ECU source code

I would imagine its akin to writing BIOS code, thats real hard core, way above (or rather below) my user friendly 4GL level.

Unread post by **myglaren** » 05 Jul 2009, 22:16

Sid_the_Squid wrote:
Maybe someone with an intimate knowledge of ECU source code
I would imagine its akin to writing BIOS code, thats real hard core, way above (or rather below) my user friendly 4GL level.

Wonder how it would run on Linux 8)

Unread post by **CitroJim** » 05 Jul 2009, 22:17

Sid_the_Squid wrote: I can’t speak for the other V6ers, but certainly my main concern stems from a paranoia about my box dying, even the slightest irregularity and I'm thinking apocalypse.

Try driving a V6 after you have totally rebuilt the gearbox Sid

Senses, all six of them, working flat-out constantly listening and feeling for the slighted irregularity

In fact these threads have helped me realise that mine is really (touch-wood) pretty good. Had it not been for the fellow V6 owners on here I would be really panicking by now, thinking the odd snatched change was a result of my work rather than being pretty much normal.

Yours is in no danger of dying Sid. It has lovely fresh, clean oil in it for one thing and for another, if the worst happens, all is not lost. Out with the engine, deliver me the gearbox and I'll deliver it back fixed

Re-writing the code in an ECU

Not something I'd even begin to contemplate. Like you Sid, my computing is carried out in high-level language and I've not been near machine code since the days of the Z80.

Stempy: Following with great interest your Hydractive ECU work

Sid_the_Squid · Unread post by **Sid_the_Squid** » 05 Jul 2009, 22:21

oh thats sooo 2006 Steve

, everyone knows Mac OS is where its at. 8)

Unread post by **myglaren** » 05 Jul 2009, 22:23

Sid_the_Squid wrote:oh thats sooo 2006 Steve , everyone knows Mac OS is where its at. 8)

I will NEVER concede that

8)

Sid_the_Squid · Unread post by **Sid_the_Squid** » 06 Jul 2009, 09:00

Out with the engine, deliver me the gearbox and I'll deliver it back fixed

You’re a good man Jim, thanks for the offer, lets hope I never have to take you up on that

Well initial test run today, sadly no changes on the low speed ‘snatches’ happened in the usual places on route. But overall the gearbox changes smoother, its back to how it felt before the first reset was conducted.
Still the most noticeable gear change has got to be 2~3, the others I don’t notice at all. Anyone else have a similar experience?

Unread post by **CitroJim** » 06 Jul 2009, 12:37

That's interesting on the result of the re-initialistaion. It suggestes the immediate drive-off to a varied set of circumstances is important. Your experience certainly bears out mine.

Sid_the_Squid wrote: Still the most noticeable gear change has got to be 2~3, the others I don’t notice at all. Anyone else have a similar experience?

Yes, I find that but only if the 'box decides to change up on neutral/slightly trailing throttle if running through a town at 30mph or thereabouts. All up-changes with plenty of power on are totally smooth.

Clogzz · Unread post by **Clogzz** » 06 Jul 2009, 14:15

In electronics, we often have electrolytic capacitors being faulty when cold, and then coming good when warmed up.
A low capacitor in an ECU may show as a cold running fault, and come good when the engine room has warmed up.

Stempy · Unread post by **Stempy** » 09 Aug 2009, 19:46

Thought I would update this with my findings. Having replaced the three suspect components on the HA ECU I can thus far report that there has been no more ratcheting of the rear electrovalve, no more randomly sticking in hard mode and bizarrely I could swear the modulation hum from the valves is quieter

Anyway she seems to be back to her floaty self.

Unread post by **xantia_v6** » 09 Aug 2009, 21:18

Stempy wrote:Having replaced the three suspect components on the HA ECU

Was it just the electrolytics you replaced? are they SMD or leaded?