79 280CE Erractic Idle Speed

Hi- We have a 79 280CE w/110 Motor. When you start the car it revs real fast, then it slows down, then revs real fast again. The oil pressure will shoot up to 40, then back down to about 30, then 40 again with it's in Park. We are going to change plugs, wire, distributor cap and button. But is there an idle speed setting that we need to be concerned with.

We are restoring this car from being in the barn "literally" for 6 years. The interior is primo and the paint/etc is great too. I'm sure we just have a few bugs and dust bunnies to flush out. Any advice would be great.

Also, the sunroof is very sluggish, you have to help it open and close. Any clues there.

Thanks in advance....

Eric D in TN.

My guess would be to start with the fuel/air mixture on the carb, and work your way to setting the timing properly.

Also, the gas in the tank is probably really stale, if you can, try and fill or top it up with really high octane gas (Sunoco Ultra 94) or something similar for the next few fill ups.

Hope this helps.

AARON ROCHARD

1976 230.4 W115

How do you adjust the mixture on the carb? Also our is the fuel injection model does this tip still apply? I have a service manual and it talks about two screws on the carb, is this what you mean? Thanks for the reply...

If yours is fuel injected, I'm not sure if this still applies, Ill check my Chilton's manual and get back to you. However, it still sounds like the timing might be off. If you're not sure about how to adjust it, I'd suggest paying a visit to your local Mercedes shop (preferably NOT the dealership, better some older guy who has worked on this model or something similar before ) If you don't have one of these in your area, try a Volkswagen or other European shop. You'll save yourself a lot of headaches !!!

AARON ROCHARD

1976 230.4 W115

Originally posted by arochard
If yours is fuel injected, I'm not sure if this still applies, Ill check my Chilton's manual and get back to you. However, it still sounds like the timing might be off. If you're not sure about how to adjust it, I'd suggest paying a visit to your local Mercedes shop (preferably NOT the dealership, better some older guy who has worked on this model or something similar before ) If you don't have one of these in your area, try a Volkswagen or other European shop. You'll save yourself a lot of headaches !!!

AARON ROCHARD

1976 230.4 W115

we sent it to a shop today. the timing was set high, we checked it with the timing light, hopefully the adjustments the shop does will help
thanks

[Benzmac]

If your car is infact a 280CE, the E stands for injection. I would think that the ilde valve is faulty. This engine has an idle valve that is coolant temperature dependent. It will decrease the engine as the coolant warms.

After the valve problem is looked at, you could have the base idle adjusted on this engine.