took my car to a place that works on mercedes
they said my fuel distributor is bad because car is running on 5 cylinders at idle #6 is dead at idle the tech swap the tubes that
feed the fuel to the injectors from 5 to 6 now dead cylinder is # 5
but the tubes are not clog. said price is $1300
so i took it off spray the **** out of it with carb cleaner and tap the side with a hammer incase there might be a piece of dirt inside of well car is now running fine but i need to know where do i put the test probes of my volt meter to check the EHA
as for i turn the mixture screw in a few times also is it in mv or ma
i know the spec is 800 but at idle or at 2000rpms
thanks jose

Use the search button at the top of the page. This has been discussed 100`s of times. You need a volt meter that reads duty cycles & milliamps (ma). DON`T touch the mixture screw until you know your starting point. You won`t get it anywhere near where it should be by guessing.

Tinker

Many posts are in the archives.

To look at EHA you will look at current (ma). To do this one must be in series with the circuit, This means the circuit passes through the meter. Proper EHA current should swing up and down about 2-3ma around zero ma when warm and in closed loop.

BTW there is a lot of junk out there and prices off the wall. This is not a part to buy in the aftermarket as Bosch's prices are outrageous. Anything else is a pig ina poke. Get the Bosch rebuilt from MB for less than 700 (I think it was 676 list for a 300E last look).

__________________
Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician

ok so which wire on the eha valve do i put my meter in series with????????? thanks jose

Unfortunately to ask such a question indicates you don't understand either current or the circuit.

It doesn't matter which wire!

__________________
Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician

You run it in series.

Three wires. Aligator clips on each end make it easier. Unplug the EHA. Wire number one to the EHA connector plug and back to the corresponding side of the EHA. Wire two to the EHA connector plug and other end to the volt meter. Doesn`t matter red or black. Wire three from voltmeter to the EHA. Your now in the loop. Read the ma.

Tinker

i did that earlier but at idle no reading rev up the gas to 2000rpm
no reading does it matter if the o2 sensor is still connected?

No amperage at the EHA usually means a faulty OverVoltage Protection (OVP) relay. You leave the O2 sensor connected.

Tinker

checking that way no reading but if i plug the eha connector back then take a reading on the dc volts scales i get 3.45volts. so today i'm going to get a different meter maybe mine is broken on the ma scale