engine idle

[n/a]

My engine idle keeps rising when I come to a stop. I hit the pedel & sometimes the ldle goes down,sometimes it doesn't. The thing is...my adjustment on the "throttle body" for the large butterfly is backed all the way off. Any ideas?

[J. Huber]

Hey Gator. Glad to see your name over here. It sounds like it could be a leak in your braking system -- I think others here have had similar situations. Do a search for things like "idle, brakes, vacuum" and you'll get some ideas...

James
63 230SL

[rwmastel]

John,

Hello and welcome to the Group!

Use the Search tool and look for "venturi".  That's a common name for the intake manifold flap unit.  You'll learn that it needs to be set right and that it's incorrectly used as an idle adjustment.  Here's one good Search result:
http://index.php?topic=1412

Does your idle rise if you have the car out of gear (manual) or in park (auto) and you step hard on the brake pedal?  I'm wondering if you have a vacuum leak in the brake system.
http://index.php?topic=4214,leak
http://index.php?topic=3101,leak

Rodd
Powell, Ohio, USA
1966 230SL, Euro, Auto, Leather, both  tops
1994 E420

[ja17]

Hello John and welcome,

If you have a USA delivery 280SL the venturi also has a vacumme idle control dashpot (governor) which regulates idle speed also. If You have this let us know and we can advise.

Joe Alexander
Blacklick, Ohio

[n/a]

Yeah, sorry! My car is a 66' 230 & it is a grey car, not U.S. but european. 4 speed. If it is the brake system, what might be the problem!

[Benz Dr.]

Gator??? ( we know each other )

 Could be sticking flyweights inside of the distributor. Let the engine idle once it's hot and check idle speed. Turn off engine and then re-start without touching the gas pedal. If the idle speed is a lot lower repeat this test again. If it's consistantly lower try driving the car around then let it go back to an idle again. If it's now at a higher idle speed or the speed changes all the time ( sometimes high , sometimes low ) it's likely a sticky distributor.
 Throttle linkage can also affect idle speed. You do have an oil can?



Dan Caron's
 SL Barn
benzbarn@ebtech.net
 slbarn.mbz.org
  1 877 661 6061