1987 928S4 - RPM Probs, HELP!

[blueblooddude]

Hi Folks!

I'm happy to report that I am a new member to the 928 family! After falling in love with my collector friend's '82 Euro S, and a year of looking, I bought a well-maintained '87 5-SPD that has everything I wanted. I drove it for several hundred perfect miles and then put it in the barn for the winter.

Here's the problem. I took it out of storage, cleaned it up, and it drove as well as when it went into hibernation. Took it to my Porsche guy...very knowledgeable and has owned 928s himself...to fix the sunroof, bleed the new clutch, get the inspection done, wash the engine, and other relatively cosmetic things. He metered the tachometer and found it to be off appx. 800 RPMs low and reset the gauge. When I picked it up, I was surprised to find that the car's RPMs shut down at appx. 4000! I mean, BAM...like flipping a switch, it drops right off to zero. It hitches but recovers when I up shift but dumps again at 4000.

HELLLPP. Any ideas? Has anyone seen this before? It's back at the shop with him, but he's a little stymied. Which makes me nervous, and it's frustrating as the car was running great.

Thanks so much for any assistance...

Jeff