2003 Citroen Xsara accelerating forward when stopping?

[Taipan]

Hi All

2003 Xsara 1.6 auto has a strange fault . If you're braking just as you come to a stop the car will lurch forward as if you'd prodded the accelerator? Its not every time but it does do it fairly regularly? Anyone heard of this before or know what it might be?

Thanks

[Zelandeth]

Afraid this isn't something I've ever encountered on a car. I have encountered a very similar sounding symptom on a bus once which turned out to be a firmware fault in the gearbox controller (it was basically waiting until you were virtually stopped then slamming it into 1st gear from freewheeling). I remember that it was incredibly annoying, but once the guy from Alison had flashed the controller with the new firmware the problem disappeared.

The first thing I think I'd want to see in this case would be live data on a Lexia to what the car thinks the throttle position is at these moments when it's misbehaving. I don't know whether the auto box on these takes an input from the brakes as well, I know that some do and an intermittent brake light switch in those cases can cause some odd behaviour.

It's an interesting fault and I'm personally curious to know what the bottom line cause for it is...sadly I don't know the systems in question well enough to be much use!