"Hi Enrico,
Thought I'd drop you a quick note, having been reading your 'Cup' letters page.
I have exactly the same symptoms as the guy experiencing the problems with his heater. As soon as the weather got cold, the temperature control went a bit strange. Mostly far too cold, with no change in temperature when adjusting the target temperature, but would occasionally have a bit of a 'fit' and blow hot a for while before returning to 'teeth chatter' mode. I suspect the internal temperature sensor is faulty (poor connections) or the temperature actuator, but have not investigated this yet.
Regarding other electrical niggles, I have found a couple a fantastic products, one of which I have bought and am very impressed with the results. It is a contact enhancer/de-oxidizer called De-Oxit, which can also be combined with a product called Pro-Gold (which further enhances the connection). It has made a vast difference to idle stability, pick-up etc. Next step is to try it on everything else electrical on the car (including the temperature controls).
It claims to not only de-oxidize the contact surfaces, but also fill in all the surface imperfections on a typical contact with a conducting polymer coating. This reduces contact resistance to practically zero, but cleverly does not short out compact connectors because the coating only conducts when in the presence of an electric field (i.e. a metal connector).
Over time, due to the poor coating on the electrical connectors (modern cars use gold-gold or silver-silver for most connectors associated with engine control) oxidization increases the resistance of the connectors. This has the result of every signal the ECU gets being slightly out from where it should be. If you think about this effect being present on every current/voltage based signal (air temp, air pressure, throttle angle, lambda sensor.....etc) you can image why cars don't always run properly.
The product is made by Caig Laboratories in the States (www.caig.com) and can be bought from Probus Electronics +44 (0)20 8866 7272.
The is an alternative product called Stabilant-22 (try searching google), but I haven't found a UK source for this, it gets even better reviews than the De-Oxit and has been given not only VW part numbers, but also NATO and NASA part numbers...so it can't be bad!
Apparently it will also make your Hi-Fi sound better!
Hope you find this useful.
Please let me know if you have any luck with the faulty temperature control question.
Regards,
Nick. |