Uneven Idle - PeachParts Mercedes-Benz Forum

Fun 380 · #1 08-24-2006, 11:06 PM

I notice that the idle on my 83 SL380 seems to surge. All of a sudden the idle seems to increase a few hundred rpm then comes back down. It keeps doing this. Any thoughts on where to start?

david s poole · #2 08-25-2006, 11:16 AM

buried behind the glove box is the expensive relay that runs the idle valve.what you are seeing are common warning signs that relay about to bite the dust.it can be had from programa as a rebuilt on an exchange basis[to ease the sticker shock] good luck david poole dallas tx.

Mike Freeman · #3 08-25-2006, 04:48 PM

At pin 9 of the idle speed control unit is input for a/c compressor engagement,Every time the a/c clutch engages the idle is raised.
Make sure you don't "fix" a normal condition.
Mike

Fun 380 · #4 08-25-2006, 07:35 PM

Quote:

Originally Posted by david s poole

buried behind the glove box is the expensive relay that runs the idle valve.what you are seeing are common warning signs that relay about to bite the dust.it can be had from programa as a rebuilt on an exchange basis[to ease the sticker shock] good luck david poole dallas tx.

How much does one of these cost and what happens when it finally bites the dust? Will the car just die on the road?

Thanks