Fault code 68 / Road speed sensor

[jsr]

Last weekend, whilst on a dual carriage way, my Chim 400 started to splutter and then cut out. It was about 30 seconds before the car restarted and was not a pleasant experience being at a standstill in the inside lane of 70mph traffic. Once restarted, all was fine again. Occassionally though, there is a slight splutter at around 2000 and 3000 rpm. The car also does the 'they all do that' stalling at junctions, though it's only happened twice in the past two months, since replacing the lambda sensors (previous to that it happened a couple of times a week!)

I checked for fault codes today and found number 68 was showing - road speed sensor output too low at medium rpm and high airflow. Speedo seems to be working as normal, so possible wiring fault, though sensor cant be ruled out either.

Have read all (literally!) of the previous topics on fault code 68 and also the road speed sensor, and consulting the bible as i type this. I plan to adjust the base idle screw, reset the ECU, then leave the car to idle until the fans kick in and see how it gets on over the next week or so. This will be the first time the ECU has been reset since the day the new lambda sensors were fitted - just want to be sure the trim value the ECU 'learns' is correct (though i'm no expert on this so don't know if this will have any effect).

It will be due a service in the next month or two, so will get it properly looked at then, though i would appreciate any more details about the road speed sensor. I know it's quite expensive, but i have no problems replacing it if need be - what is the part number?

James
www.jsread.com/tvr

[jsr]

Did all the above, then went out for a long ride for a topping up of Optimax (104.9p :O). Strangley, the fault code is no longer present. Guess i'll need to check again in a week or so to see if it returns.