I've got a 91 190e 2.3 It recently has had a rough Idle/ low idle---'round 500 rpe. Any suggestions?

Hi-Haven't been around for a while, scrolled sites-I just started same thing today! I'm blaming it on a half tank of gas at a station I never go to-I was fine until shortly after that. I left tank at 1/2 full and dumped in a bottle of injector cleaner-stopped hard,swung around corners to stir it up a few times (didn't want to dilute w/ more gas)
I've put on 15 miles and haven't noticed a change yet.
Maybe we have the same problem? Have you tried fuel additives? How are your spark plugs, wires etc.? Fuel filter? These are all things I should attend to-NO TIME (!)
Keep us posted-Good luck!
-M

Idle speed is controlled at the rotary idle air control valve stuffed between intake runners 3&4. Pull its plug and see if the idle speed changes - if not, do a search here to find out why. The OVP fuse may be bad, disabling the ECU, the throttle position switch might not be making contact, the linkage may be hung up, the ECU could be bad, or the valve itself could be gummed up or no-op - to list a few.

Steve

Thanks for info!
Are these cars overly complicated or is it just me? It's an 85 for crying out loud! I would think a lot simpler!!!!
-M

"Are these cars overly complicated or is it just me? It's an 85 for crying out loud! I would think a lot simpler!!!!"

'Simple' would be in relation to what you are accustomed. If, like me, you are used to American/Japanese carburetion and pulsed injection, then the CIS Bosch controls are certainly different. Still, all the functions are basically the same. You just need to understand how it is done, and it makes perfect sense. Also, my response was for the '91 - I am not sure if your '85 has a rotary idle air valve.

Steve

Thanks for your reply-I suppose I think they're complicated because I don't do much work on cars, The last cars I worked on were my Peugeot 505 turbo diesel's, Miata (basic maint. ) very simple.
I read posts on this site trying to learn and perhaps share a tid-bit of info. Everything is way over my head!
I'm planning some basic tune up jobs this week-end, Spark plugs,wires,rotor,filter (air), fuel if not too hard-just basic stuff I can handle. Will see what happens and go from there.
Thanks again-Mel

Keep us posted.

There are great resources on this site. It is amazing what people have done to solve problems with their cars. Since too often the same or similiar problem has already been solved by the members, keep asking.

... and keep us posted!

Haasman

__________________
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)

Thanks- I will! It reall is a great site-lot's of support/info-must do searches more.

I thought I was the only one up this late!

The 190 ran VERY poorly and it turned out to be a bad rotor/cap and also clogged injector lines. I bled them and it made a world of difference. More on that later.

I'm a night owl ...

Haasman

__________________
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)

Thanks for the tip.
Funny I erased my previous post stating that I forget the West coast is a little earlier than the East! I should know better! My parents live in Desert Hot Springs! (Ca.)
I forget this is the WORLD wide web It's after 1 A.M. here and alarm goes off at 7:30! NOW who's the night owl!
Thanks for your input-everyone is so helpful!
-Mel

Before you do anything else, I would look at the idle air control valve like sbourg said. I have a 190E and I took it out and cleaned it as well as I could with brake parts cleaner, then lubed it with WD-40. I haven't had a problem with the idle since. IT's kind of tough to find it if you don't know what to look for, but it's the pump looking thing encased in a rubber "Holder" sandwiched between the 3rd and 4th intakes. Email me if you don't find it. Just yank it out

Thanks guys-now if I can only find some time! Don't get me going on the lawn and the new pin-hole leak in rad. hose!
I need a vacation just to get caught up!
Thanks again for the help!
Take care, -M