This happened once yesterday, then again today.

I pull onto the freeway and accellerate. At about 60kph my RPM's drop by about a grand, even though I continue accellerating.

Anyone else experience this? It's like the reverse of a slipping clutch. Vacuum leak, maybe?

 

or a messed up tach

 

I think the tach is sticky.

Mine is sticky right now too, but mine sticks when it's coming down from to idle. Instead of sitting at 900 rpms or so, it sits up @ about 1500.

Yours might be high at idle and then when you accelerate (after a certain point in the tach) it settles back into to normal.

 

Weird. I've got a Sun tach II that sticks at 3k RPM for a little bit after you rev it up and let it settle back to idle.

 

The tach isn't sticking - as I said the RPM's DROP. I not only see it on the tach but hear it in the revs.

 

are ya 5 and 6 port, blocked?

 

hmmm... worth investigating.

 

I talked to a dealer one time that said some of the 1st and 2nd gens experiences an rpm drop around 3000k becasue the primary ground wire came loose. You might want to check this and scrape any corosion off it.

 

Well there's your problem,lol

 

You have a magical overdrive.....

You got me stumped on this one.
Which gear were you in? Is your timing advance working? Keep us up to date.

 

I'm thinking slipping clutch.

I was in 3rd gear