Can anyone tell me how to read the fault codes on the Mk 4 Golf? The idle is a bit unstable, but if fast idled at 1,200 rpm with constant throttle pressure, the revs suddenly build to 2,000 and drop to 1,000 as a repeated hunting cycle. You can feel the throttle pedal “kick” when the revs drop. The air intake was contaminated with oil, so I’m suspecting there might be oil in the idle control valve. I’ve found the 16 pin connector (beneath the ashtray) but I’m unsure of a) The correct connections. b) Which light will flash to give me the codes.
The car is a 1.6 auto 8 valve and has done 40,000 miles.
Also, does the auto-box require an oil change? I can’t find a dipstick or filler plug. I did ask this question of my local VW main dealer but was told they weren’t sure! Perhaps it is a “sealed for life” gearbox? If so, does anyone know how long “life” might be?