Dangerous fault
 

Hi
We've had my wife's 75 connesour from new ,2003. She loves it and refuses to get something new.
Last fortnight she's really anxious driving it. Three times now she has started braking and the car has accelerated,really shook her up.
My pal plugged her in and got gearbox fault reading.
On another internet site I found some Kia owners had had the same problem.
Not finding anything obvious ,tonight I am dropping the gearbox fluid and changing it as it smells awful and hasn't been ever been touched in 87000 miles.
I'll report back on results.anyone else had this problem?

I'm not sure how a gearbox fault makes the car accelerate (as in opens the throttle unexpectedly) I'd be looking at the pedal box - and the throttle position sensor (it's diesel isn't it?).

Had the car from new? Gearbox fluid should have been changed back in 2009 and again in 2015 - interval is 6 years/ 60,000 miles whichever comes first: I'm not surprised if it smells.

Unless he cleared the fault and it re-occurred after the fault happened again it doesn't mean anything. Add to that the 2003 CDT isn't 100% OBD compliant, so unless it was a T4 he plugged it into... Add to that there's a list of things that come up as faults on these cars that are normal and only experienced operators can tell you which. I'd take that fault reading with a pinch of salt. Still, change that transmission fluid!

My money is on throttle position sensor or catching the throttle pedal with foot when braking.

If it is a diesel then I would seriously look at cleaning out the intercooler, silicone pipework, egr valve and inlet manifold... you may have a buildup of oil which is feeding the engine and causing the surge...

Check your engine oil level - let us know if it is too high.

Sticking EGR might be. If it was either of the other two it'd probably runaway rather than just surge.

Just a thought but seeing as the servicing hasn't been stellar: has the PCV filter ever been changed?

Most common problem is people thinking they're on the brake pedal, when in fact they are on the accelerator, easily done in a lapse of concentration.