I think my EA (ETA) is going bad '94 E420
 

Hello folks!

As some might recall, I was having a few codes come up on my E420.

At that time, I noted a buzzing sound coming from the middle of the engine, but couldn't really narrow it down any. Well.... I gave it a closer look, and have decided that it is the electronic throttle actuator that is making the noise. It sounds like a gear isn't catching a tooth - Once I moved the throttle linkage a little, it sounded like it would catch and the sound would go away.
I am guessing that some gear isn't able to close the throttle plate all the way anymore, but, if I move the throttle cable a little (wether by hand or foot), I can get it to catch.
Any opinions on this guess of mine?
Is it time to look for a new/rebuilt EA (ETA) ?

Thanks,
-Larry

Larry, not sure the EA noise is diagnostic of your code issue. My M119
EA has "buzzed" (noticeable with the air cleaner off) for the two years I've owned the car. No codes, runs perfectly.
One of the techs here may know what causes the noise, but don't think its unusual.

ETA noise
 

Larry the noise you hear coming from the ETA is normal. The sound coming from the ETA is produce by the unit as it begin to set the throttle plate into the proper position before your engine starts. As you turn your ignition switch to 2 position, the ETA utilizes the info from the engine tempeture sensor to set throttle plate. You can try and adjust the throttle plate by hand but it will only go back to it proper factory preset position. The throttle plate should not close all the way doing start. Hope that helped...

Just for info...a HUMMING noise is normal from the EA with the key on.....A ratcheting noise is NOT normal & is a sign that that throttle actuator has a PROBLEM.

Right-on, 100%! Well, we agree about that! :)

Well...It's definitely doing more than just humming. It sounds like a little electric motor with a gear, trying to catch another gear.

There's also the fact, that once I move the throttle, the noise goes away (I am assuming the gear got caught).

I am thinking that the throttle plate is not closed all the way, and that at the same time, the engine is getting extra fuel.
Cold starts are fine, drive off is good for about 20 seconds, then I get a hesitation/stumble for a moment or two. Warm/Hot starts are no longer instant or near instant... I have to resort to stepping on the gas a little to get it to start.
Since my discovery of the noise, and how to make it "go away" by stepping on the pedal prior to engaging the starter, I have been able to get satisfactory Warm/Hot starts.

I don't suppose there are any user servicable parts inside, are there? (provided I can extricate the thing)

Thanks!

-Larry

They are available ONLY as a complete unit....new ones are made by VDO...sold new by MB & other MB parts outlets.

There are remans out there for about 1/2 the MB list pricing..

Thanks Doc!

btw.... where do you get your reman'd EA's from ? :D ;)

(there's a place in Pompano bch that is selling some on ebay....ever hear/deal with them?)

Does Phil carry reman's?

Thanks again!

-Larry

Check out my ASR page (Menu#24) showing some re-mans.

I've just completed a 'refurb' of the one shown in Menu#24; the one from my car. Will document with pics and what was wrong in the near future.

From the feedback I get, one of the best reman job comes from "Beckmann".

Try www.4mercedes.com , I got my rebuilt TBA and its worked wonderfully!

Chris

Update
 

I took the car into the shop, to have the blower speed regulator replaced (left it there the night before). Apparently, when they started it, to bring it inside the shop, it backfired. They hooked their reader up to it, and it came back with a bad Air Mass meter. So, I gritted my teeth, and said, to go ahead and replace it. A few days later when I picked up the car, I was told that all codes are cleared except for 1 (he wanted to disconnect battery to clear it 0 said his gadget wouldn't clear it for him). I told him not to worry, I would clear it at home.
Once I got home, I checked the code (it was the high module temp one) and reset it.

It's been several weeks now, and not one code has shown back up!

Sure, I am very happy about it....but, it does raise the proverbial eyebrow, as to why them other codes were there to begin with - UNLESS, it was because the high temp was making it go bonkers and had it spewing out codes. (now that the A/C blower works again, it is probably keeping the temps down).

thought, comments, opinions?

-Larry

(For some reason I typed O2 sensor - just realized my error, and changed it to AMM) ooops!

Glad it's fixed . . . w/o the expense of a new ETA. Hope it stays that way.

Keep us posted.

I'm glad it's fixed too - But that Air Mass Meter isn't the cheapest either :eek:


(I mistakenly wrote O2 sensor when I first wrote the reply - doh)

MAF are on the expensive side. An O2 sensor is cheap by comparison. Actually both are the best to "help" an older MB. I changed both of them about 2-1/2 yrs ago and it helps the S/A maintain a "close-to-1" lambda.

In my experience, it's rare that an 'older' MB comes up with a failed MAF as compared to the later models. It's almost a regular replacement.

I changed both about 2-1/2 yrs ago and it helps the S/A maintain close to "1" lambda.