Hi everyone,

I have am having problems with my throttle control on my 4.2 l, 92 400E. Poor idle and acceleration quality between 500 and 1500 rpm. I have looked at the cap and rotor, their fine. I have changed air filters and have changed the fuel filter before a fuel injection cleaning last year. So now its acting strange as noted above. From what I have read from this bulletin board I am leaning on either just getting by with a good cleaning or replacing altogether my EA on the throttle body.

So can i remove the throttle body?EA as per the instructins in the cd manual or are there some tricks i need to know. Once off, how do I go about cleaning the assembly without damaging it. What cleaners can i use etc???

I have read where a member had the assembly cleaned and then it was re-installed. It seemed to work out ok for them.

Anyways this board has been a great help for me over the past so if anyone has some good ideas regarding the above please let me know.

I'll try to return the favour

Davef

If you take off the mass air flow sensor it's pretty easy to clean up the engine actuator/throttle body without taking it off the car. To remove the air flow sensor you just disconnect the wiring plug, then loosen the 7mm worm screw at the bottom a few turns, then pull up on the sensor body. The 7 mm worm screw is quite tight so you may have to remove the vacuum pipe for brake unit to gain enough room to get at it. The vacuum pipe nut is a 19 mm or 3/4 inch, and you really need a crows foot to get it. When you get it all apart just clean up the butterfly valve with carb cleaner. You can do the same for the hot wire on the air flow sensor. If the rubber grommet between the air flow sensor and the engine actuator is cracked or bad you need to replace that - about $20 at the dealer. Not really a tough job - just very tight quarters.

thanks for the info...well I tryed to take the MAS off and what a #@$^!! I couldnt budge it off its rubber gasket. Even with everything lossened off or removed. So with out actually damaging it I decided to take it in to the shop to be properly diagonised before I break anything.

thanks any ways

dpf

You've got to turn the 7 mm nut until the hose clamp is plenty loose, and then just rock it back and forth until it loosens up a bit, then get some upward pull on it. It's probably been in there since the factory put it there.

ok

I will try it again, once i get the diagnostic done on it

dpf

i have lost 3 small screwdriver bits tryin to unloosen the clamp

ill get them later...

FYI I recently did this replacement. If the rubber interface is original you likly will need to destroy it to get it off. On mine I completly undid the hose clamps - thing wouldnt budge. Had to cut bits of it off then I finally got it free. The replacement is relatively flexable so putting the new one back on is no problem. Age and heat cause the problem.

I went throught the cleaning process but in my case it did no good. Needed to replace the throttle actuator aka throtle body, aka EA, aka ETA. Mine was throwing fault codes.

Good luck
Paul

well folks... case closed!!!

I took it to a star one mercedes dealer where i buy most of my parts. They did the diagnoius on the vehicle and my ea was shot and the brake switch had to be replaced. I felt after all the work involved trying to get the equipment off and clear the codes and keep the parts warrenty and service valid I would let them complete the job.

With some parts.... EA included...and the shop labour bill was $2k and change. Considering how important that EA setup was I made the right move. The EA alone cost $1300 with their discount in canadian dolars. Now the car moves smartly, fires up NP's in any weather and we have had it all up here recently.

So sometimes it does pay to have the pro's do it and be assured your benz will keep on movin on.