Seems to be running right at or slightly above 500, according to my onboard tach (which isn't bad I think). Yesterday I had been driving it for a while and driving it a bit 'spirited' and when I would stop I noticed a couple times going below that. When it did, the needle was moving up and down between say, 375rpm and 425rpm. It never acts as though it will die but, as stated by me before, making that ever so slightly adjustment on the EHA did change the idle to *somewhat* slower.

Dale

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Dale

How does the economy gauge register when idling at 500rpm vs below?

Sixto
98 E320s sedan and wagon
02 C320 wagon

Highest economy....

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Dale

The BAR has identified the M103 as "high emitter profile" and they have to be tested at "test only" stations.

You can get much better passing margins by plugging the vacuum advance line and shorting the R16/1 resistor socket... more info in threads started by me a few years ago... easy search.

BTW, the DMV finally "fixed" the computer program so that '76-up Historical Vehicle plates have to be tested. Oh well, the "exemption" was great while it lasted.

I just had my '88 190E 2.6 tested for the first time in four years, and it passed with good margin. SEMA/SAN is aware of this and will work toward getting all HV licenses vehicles exempted. AB 210 was introduced last month and amended this month to increase the model year exemption from '75 to '83, but given the current extreme left wing super majority in both the Assemble and Senate...

More info at the following link:

Bill Text - AB-210 Smog check: exemption.

Also, it's my understanding that Friday, Feb. 22 is the last day that legislation can be submitted to be considered this year.

Duke

I've owned my 1991 MB 300-SEL since April 1997. Not too long after purchasing, I had a former dealer tech(now Indy) install a new water pump(OEM) and do some adjusting in/around the EHA/Fuel distributor. In 2003 - this same tech installed a new head gasket. It was not leaking or blown - but nearly 13 yrs. old. I decided to do it as a preventative measure. In 2010 I fitted a new belt tensioner myself - good intro for when I finally have to swap in a new water pump.

Nearly 22 yrs. later that same water pump is still doing it's job and there has been no adjustment to any part of the KE system. The car has always started right up, idled very smoothly and never bogged down on acceleration. I'm now dealing with a ragged start-up-when-hot issue, but went thru this yrs. ago. A new accumulator took care of this. It's likely time for another.

I've done my own maint. over the years - all of the usual fluids/filters/fuel system/ignition system maint./brakes/cooling system/etc - more often than the book calls for.

About 2 yrs. ago - I had to finally replace the original O2 sensor - threw an O2 sensor code which I determined using a ebay sourced tool - count the blinks - look it up in a Bosch/MB document.

Having read countless complaints about "poor idle" issues on this forum over the past 20 yrs. - I consider myself lucky.

I could be wrong, but I can't help but wonder if some of these problems were self-inflicted. You read about people purchasing the 3mm allen tool and the EHA elect. connector. How many have shot themselves in the foot turning that allen screw/etc. w/o a "thorough" understanding of how this system works.

Funny thing - I have those tools just mentioned and have never used them. I sometimes subscribe to the theory "if it ain't broke - don't fix it.". One of these days I will likely have to break out those tools and fix an ailing KE system.

Until then, I'll just keep on truckin' - hope everyone here does the same.

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Mike Murrell
1991 300-SEL - Model 126
M103 - SOHC
"Fräulein"

Sounds as though you have a well sorted machine! Actually to be fair, mine is too. Been owner a bit over four years now but never drove it much until it became my 'beater' about five months ago (feel bad calling her a 'beater' because it's actually a pretty nice car).

The internet is a fool's playground when it comes to 'searching' almost any subject. Usually there's more info than needed, some very good some not so much. When I come across something that strikes a chord with me regarding whatever I'm pursuing, I dig deeper and then decide if makes sense or not. That's what got me into this - sorta. I'm glad I tweaked the EHA because my car has never ran as good! This "idle" thing really isn't anything terrible but here again, I'm looking for the "holy Grail" - an old MB performing as she did "back in the day"! And I believe I'm getting veeerrry close

Thanks Mike for your story

Dale

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Dale

I have Kent Bergsmas' tuning guide from when I bought a tuneup kit from him a few years ago. I scanned the relevant pages for the 3mm adjustment on the fuel mixture adjustment. It is only 4 pages but too large to upload here. I can email it to you if you like. He does say that this will affect the idle as well as how smooth the engine will run, I do believe though, that it is best to check the duty cycle with an ohm meter while doing this, not sure though.
Lemme know if you want it.

Well thank you! That's mighty neighborly of ya

If you don't mind doing that, I'd sure appreciate it. I can PM you my email address.

Dale

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Dale

We gotta keep these old gems running and looking good to show the world what a real car is! And what they have been missing.

Haha, that's true! Or maybe not, let's keep it a secret so they won't start disappearing !

I don't know if it's just getting old(er) but I seriously couldn't care less about driving a car that is as old as what these are because I know what they are. Never in my earlier years of driving would I have believed that I would actually by a car and keep it for ten years, yet that's how long it will be this year since we bought the '95 wagon. It's been a bit over 4 years since I bought the 260E and I'm just now getting to feel like it is possibly going to be a long term relationship as well.

And then there's the OIL LEAKS

Dale

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Dale

I'm hoping the same...somewhat.

But, quality parts availability for these cars is quickly becoming a thing of the past. More and more OEM is disappearing and more and more made-in-China POS URO/Febi/Meyle are becoming the order of the day.

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Mike Murrell
1991 300-SEL - Model 126
M103 - SOHC
"Fräulein"

There's also a throttle cable adjustment on the throttle body, though I believe it requires the removal of the metering unit and fuel distributor assembly. You can adjust it such that it'll hold the throttle open a little bit more at idle to increase the revs, though I wouldn't say it's the best solution to fixing idle problems. I adjusted it on my 190E when I put in a 3.0L M103 and when the engine is cold it keeps the revs around 750rpm but it'll rise to nearly 950 once the engine is warm and will hunt up around 1200-2000 in park or neutral after a drive. Not really a huge deal for me but it's certainly not correct.

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Current: 1975 450SEL, 83 300D, 88 Yugo GVX, 90 300D OM603 swap, 91 F150 4.6 4v swap, 93 190E Sportline LE 3.0L M104 swap, 93 190E Sportline LE Megasquirt, 03 Sprinter, 06 E500 4Matic wagon.

Speaking of the throttle cable and linkage and such, how do the ball and socket connections come apart? Does one simply pull them or pry them apart? I need to lube mine

Dale

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Dale

I would play with nothing on the electronic fuel system side .And start with replacing distributor cap, spark plugs , along with a rotor arm, and ht leads .You will find this alone will speed up the engine .The economy guage should be pegged to the left on tick over .

Romove this from the engine and give it a good clean out .But do check that rubber pipes are back in place under the metering unit.

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