I know it's not a Rod but,

Hi guys, I could use some help on a problem I am having with my wife's car. It's a (dare to say the name!) mercedes with a v8. It has been unused for a few months. When I started it up the idle is very high, about 1800 to 2400 rpms. I can't find any vacuum leaks. Any ideas? Thanks for any help......CR

A friend an I went thru this with his 76' 450 SL. He does'nt drive it very much and the valves and springs(this has an overhead cam) were real gummy. Pulled the valve covers and sprayed them real well with DEEP CREEP. It put tension back on the springs. He also dicovered the timing chain tensioner was bad. This is hydrauilc pressured and tensions the chain which is one continuous chain for the cams on both sides. Your timing is referenced off one side. (passenger i believe). Whatever you do make sure to NOT let either cam rotate independant of each other. Its a tricky fix. Invest in a repair manual it will show step by step adjustments. The cams also have an "offset key" in them. This is also common for them to go bad. Hopefulley in your case just a cleanup will solve the problem. Good Luck!

P.S. My buddy has th instructions on adjusting the timimg if you need them.

You didn't mention if it's fuel injected, but if it is, I'm betting on the idle air valve being stuck or siezed. Not sure if you can get into your's or not, to check if it's free to move.

Sniper, Where is the Idle air valve? And yes it's fuel injected. Thanks for the help....CR

Old Gold, It's running good, it just idles at 2,000 rpms. It's a bear popping it in drive!........CR

Totally destroyed!

Dude... u have totally destroyed this car & it will *never* work properly again. I will be by tomorrow to pick it up & dispose of it properly for ya!!! Real shame!!!

BoB

Dude, You'll have to take my wife too, this car is the only one she likes. I think she cares more about this car than she does about me.....LOL

CR55 said:

Dude, You'll have to take my wife too, this car is the only one she likes. I think she cares more about this car than she does about me.....LOL

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Whoops... mite b a deal killer. Doubtful Mrs Tipper would approve... looks like u're just gonna have to deal with it!!!

BoB

Air idle should be located on the intake. Usually, a small electric motor driven plunger, that will throttle the air as needed to keep the idle where it should be. Think of it as a controlled leak! You won't be able to see the plunger, or the motor if it's under a cover or shroud, but it should be a bolt on item. I haven't worked on a Mercedes in years, so I can't say where to go from here. You'll have to get a manual, or someone more knowledgeable on your car from this point. Sorry I can't be more helpful than this, but I still think you'll find your problem at the air idle, and it's likely stuck to far open. Best of luck, Sniper

Ok, Just did a quick net search, Googled "Mercedes high idle" and came back with a whack of info. Apparently this is a common problem, with a 50/50 split on whether it is going to be the valve itself, or the computor chip. Chip is seperate from the main computor so it seems. I went to Images on Google and they show the air valve, so you'll have an idea what to look for. Seems to be a lot mentioned about cold solder joints on the control boards, but people are fixing the problem themselves a fair amount of the time. Hopefully, this can get you steered in the right direction. Just follow up on those, or simular links, and you should be able to get it figured out. Best of luck. Sniper

Sniper, Thanks for the info. I seem to have a couple of other problems too!
Hopefully I can get them straightened out..........CR

fixed!!!

. Thanks guys, I appreciate all of the help with my non rod mercedes. It turned out to be an overload protection relay. It caused the engine to idle at 1800 and run rough. Plus the abs system quit working. ...my marriage is saved ...CR