Hi all, my 1990 N/A has developed a fault where when overdrive is switched on and I am cruising along, if I lift off the gas the revs go down to an idle almost immediately, then if I accelerate again the revs build back up to normal, this doesnt happen with the overdrive off, any ideas? I have spoke to Raydetinu who had a similar fault so I am pretty sure it is electrical but anyone else know of, or experienced this that could give me some more info to work on? thanks, Richard.

Its normal. Revs pretty much can drop to 700 at speeds below 40 ish but not quite so low on higher speeds, at least on mine. At much higher steady speeds you should be on locked up clutch and no fall in revs.

 

When OD is off you get engine braking but not when OD is on.

You could have a look on here mate, how to run

a diagnostic check on the autobox.

http://www.twinturbo.net/ttnettech/autodiag/autodiag.html