Engine RPM on engine start.

[steve20186]

1999 C2 6sp, 78k miles

Mornings and if I leave the car for several hours, the engine starts by revving to exactly 2000 rpm then immediately comes back to rest at around 800. Other times when it's warmer, it will rev only to like 1000-1200 or so, Is this normal?

All I can think of is that the immediate jaunt to 2k is hard on the bearings. :unsure:

Edited September 24, 2013 by steve20186

[Mike Petonic]

I've got the same issue in my '04 TTx50. I think Loren was correct in identifying it as a vacuum leak, but the same symptoms.

Here's additional detail:

• Same as yours, when the engine is warm, it doesn't happen.
• If I press hard on the brake when it starts to "surge", the RPMS go back down (this is what led Loren, I believe, to think that it is a vacuum line).
• It settles back down after about 1/8 of a mile.

Net net is that I don't worry about it anymore. I just press hard on the brake when I'm done with my first back-out of my parking slot. By the time that I get to the card reader in the garage, it's back down to normal, mostly.

[sjg1138]

old

Edited August 19, 2020 by sjg1138