I have been working on my 91 RS with 3.1 V6 recently and have been driving it about every other day. While driving around 40mph or so I notice the RPM is at 2K. I dont remember the RPMs being that high only going 40 (its been 8 years since it was a daily driver). I can remember going around 60mph with the RPM in the 2K range. The overdrive is definitely working.

I think it is a tach issue since the actual engine "noise", if you will, does not sound like its revving this high. What I mean is the overdrive kicks in around 40 and the engine sounds low like it should but the tach is reading 2K.

Am I making any sense? The car runs great and is as responsive as a 160K V6 could after sitting for 8 years, it just seems very odd.

Any ideas?