Is it the throttle actuator or the persistant ticking noise?
 

I recently had the throttle actuator replaced on my E-320. The car ran better for about a day, then the check engine light came on and it began acting as it did before: slight surging at stop-lights, no cruise control, mis-firing upon heavy acceleration. I figured the used actuator I bought was bad and made an appointment to have my mechanic check it again.

Today, none of those symptoms were present. The check engine light is still on. One more thing: for quite a while there has been a persistant ticking noise eminating from behind the dash on the passenger's side of the car. Today, the ticking was gone, along with all the symptoms I listed above.

Could the problems I've been having be due to something OTHER than the throttle actuator? I'd love any advise before I replace the actutor with a more expensive refurbished one and pay the labor all over again.

Thanks!!

The dealer can read the codes
 

I just had my kickdown actuator (solenoid I think) replaced in my transmission on my 1995 E320 because the check engine light was on. I didn't have any symptoms, but the dealer fixed it and the light is now off. They also replaced the Bowden cable and some seals inside the transmission. Maybe there is more wrong with the transmission than they fixed. I think there can be simple adjustments for the Bowden cable that cause issues too. Maybe it is just a simple adjustment. The dealer should be able to plug you in and determine why your light came on again.

I had ticking once before and it turned out to be a bad battery that the electrical system was trying to keep charged. The bad battery never made my check engine light come on, however, so I don't think the two things are related.

Yeah, my mechanic has been plugging in to read the codes too. I know the throttle actuator needed to be replaced because it was also making a lot of noise. But I replaced it with a used one, so that one may be bad. I'd just hate to replace it again because it's not a cheap fix!

BTW, should you ever decide to sell your 320, let me know!

actuator
 

make a small slice in the actuator cable close to the unit, and see if the wires are bare or have severe damage from engine heat destroying the insulation, when you buy a used actuator you likely are getting on in as bad shape as the one you are replacing, if the used one was working on the donor engine it is likely that once it is removed, the wires if they are burned will move and eventually touch, if they do they could eventually cause damage to the cruise control/ idle control module.

Thanks for the advise, guys!

I took my car to the mechanic's today and he ran the diagnostic on it. Came up as the throttle actuator again, so I will be replacing it with a refurbished unit rather than a used one. He said it was also causing the ticking noise from behind the passenger side of the dash.

Hope it works this time!!

As far as I know, there is no such thing as a refurbished unit.

Potomac German Auto, in Frederick MD sells refurbished units. I talked to them yesterday and they said that they send out used ones to be refurbished. The difference in cost is about $300.

Used: $425
Refurbished: $750 or so

I'm not sure what to do, as I've already bought a used one and had it installed, only to learn that it was also bad. It has a warrenty, but I'm out the cost of labor from my mechanic. I'd hate to have another used one go bad on me and lose the installation cost again!

So I have to decide on a used or refurbished unit. What do you think?

rebuilt actuators
 

the company below also supplies quality rebuilt mercedes control modules, including actuators and instrument clusters

http://www.beckmanntechnologies.com/catalog/IconWebPage.asp

I would be incredibly hesitant to buy a refurbished unit.

One of the rearsons they fail is due to failure of the insulation of the wiring.

Jim F. has posted pics of what these look like opened up internally, and I would find it impossible for anyone to completely rewire the internals of one of these units.

Not impossible...merely time consuming...see my web site...

http://v12uberalles.com/throttle_actuator_rewire.htm

By the way, Beckmann charges QUITE a bit more than $750 for their rebuilt units.

rebuilt actuators
 

this company replaces the wiring when they rebuild the units, not much of a rebuilt unit unless the wiring is new, i don't know how they do it, just that all of theirs i have seen have new harnesses.
someone had to wire them initially, so it is definately possible.
just because you would find it impossible to rewire it, doesn't mean that every one would.
http://www.beckmanntechnologies.com/catalog/IconWebPage.asp

here is a picture from their site, it is of a rebuilt unit

actuators
 

the $750.00 quote was for Potomac German Auto, not beckmann, i think beckmann wants $877.00

Maybe it's too . . .
 

. . late, Stefano, but take a look at MENU#24 on my web page. There's info that you should 'consider' BEFORE you do anything.

You guys are GREAT!!

I've decided not to go the extra bucks for a refurbished unit and will buy another used one for a lot less.

Jim F: thanks for the info. Luckily my car doesn't have the ASR, so it shoudn't be a factor.

Just have one more . . .
 

comment. I'd hoped that you would have seen the underlying msg in MENU#24. Maybe you did and have chosen to ignore it? Maybe because of ASR, you might think that this may not apply to you?

If you are going to replace it and, this is important, most likely you will not need to replace it again, then why not have the unit refurbished (at Beckmann or wherever) or spring for a new one?

The underlying theme in that Menu#24 is the problem with the Ref Pot; it CAN'T be repaired and, as you saw, many who have undertaken the re-wiring of the unit, have not had success even though the wiring was done well.

Now, so far, the ones that had them refurbished have sent good reports. So at least maybe consider that avenue??

My LAST $0.02.