tewfiks

Hello All:

Recently my 91 964 C2 cab has started to act up. When I depress the gas with any gusto the engine will rev up before accelerating. This occurs when the car is already in motion, not from a stand still.
What am I dealing with? The car otherwise has been behaving perfectly. Something with the ignition? The clutch? Any advise would be much appreciated.

Navaros911

Without more info I would say it sounds like a clutch thing.

Manual or tip?
Happens in all gears or only some?
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spartansix

So if I understand correctly, if you are cruising on the highway in 4th and go hard on the gas, the revs increase while the speedometer remains the same?
This sounds like a slipping clutch to me.

tewfiks

Sorry forgot to specify that it is a manual transmission car.
I was leaning towards a slipping clutch.
Yes, if I am at speed and give the car anything more than a minimum amount
of gas, the engine revs increase before there is any actual acceleration .

r-mm

Certainly sounds clutchy to me. Before you presume its the disc itself slipping - which usually smells very distinctly - check the hydraulics. Start by making sure you have adequate fluid then do a bleed. The soft lines can swell and cause strange things to happen. Is the pedal nice and smooth / no noises from the transmission when you depress it?

Navaros911

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This and check to see if your clutch cylinder is not leaking. It is bolted up to the tranny and has the bleed nipple.

I replaced the hose and cylinder on mine when I had similar issues and got another year out of the clutch. This is a medium DIY job, as bleeding is not so straight forward, where the clutch replacement is much, much further up the scale.

tewfiks

No strange sounds from the clutch pedal, functioning as it should/normal. I had the clutch cylinder replaced a few years ago.
I will take a look at the lines, but will order a clutch kit in the not so distant future.
Thanks for all the input

95_993

While you looking at things, make sure there is no oil/wetness where the trans meets the engine. You want to be sure you don't have a small RMS leak. Even the slightest bit of oil on the clutch will cause slipping. You will want to address when you do your clutch..