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-   -   m104 rev power problem (http://www.peachparts.com/shopforum/tech-help/360078-m104-rev-power-problem.html)

244brick 09-22-2014 02:16 PM

m104 rev power problem
 
1994 e320 estate, 144k

Was doing about 60mph and lost throttle response. Car didn't shut off, but now it idles at about 1100rpm and kicks back like a rev limiter at 1500rpm, in gear or not.

Bad throttle actuator?

tecqboy 09-22-2014 05:06 PM

If you have an OVP relay, check the fuse. OVP = Over Voltage Protection. The fuse blows to protect electronic components from high voltage. Vehicle goes into limp mode if fuse blows.

244brick 10-03-2014 06:46 PM

Finally got a chance to look at the car. The 15a fuse is still intact.

oldsinner111 10-07-2014 05:43 AM

check to see if crank sensor is plugged in good.

244brick 10-21-2014 06:16 PM

Ok so, I checked the crank sensor and it seems to have a solid connection. The wire is bare, so it has seen better days. I pulled code 17 from the code reader which is 'communication failure between control modules' or something like that.

ILUVMILS 10-22-2014 12:04 PM

Sounds like the throttle actuator and/or E-Gas control module. Have it checked for fault codes.

oldtrucker 10-23-2014 11:41 AM

Does it have the updated wiring harness?
Also, the wiring from the Throttle Body, can be bad, e.g. shorting out with outher wiring.
The 1100 RPM idle, if the wiring (throttle body) is bad, it has the ability to take out certain inputs on the e-gas computer.
Only way to find out, is to cut the sheath open and see if there is anything left from the insulation (ECO Junk). YES, the throttle body had ECO JUNK too.
The symtoms you describe, do fit a bad throttle body wiring!
That crank sensor, I would replace it asap, along with any other blank wire(s)!

244brick 11-21-2014 10:50 AM

The only contradiction i have with the throttle body/actuator theory is when i first start it up on a cold block, it will rev as high as I want at least once and then throttle response over the 1100 cuts off after that

244brick 01-17-2015 02:39 PM

1 Attachment(s)
Ok! So finally I got some free time to dismantle the wagon. I took off the ETA and found loads of corroded wires from the green board back to the loom. Sorry for my endless questions and thank you all for the great help! I'll be doing some rewiring now. :)

244brick 01-17-2015 06:05 PM

Ive ran into a problem. I went off the benzworld thread, and I cut open the loom as J.M. van swaay did in the pictures, but the pin carier is definitely inseparable.

Is there a wiring diagram for these? When I heated the solder to remove the wires from the green board... i kind of lost the numbers

oldtrucker 01-18-2015 01:10 PM

1 Attachment(s)
Hi, 244brick,
from the image, it looks like there is the ECO junk wiring in the TB.

Altough, rewiring is possible, there maybe a number of problems showing later and during. One of them is the clutch that holds the flap in position while using the cruise control. With corrosion that bad inside the housing, my best guess is that the clutch plates are corroded too. It is questionable that the servo and the rehostat is working properly, either. Also, it is very difficult to seal the wiring at the entry to the TB.

The elevated idle, may indicate a short of the idle micro switch inside the throttle body or at wire somewhere. The ECU / FI doesn't see the switch at correct state and acts as if the accelerator would be depressed.

My advise, look at Fleaybay and locate / purchase a used one made after 1996. They can run between $200-$400 used. Of course there is always a way to purchase a refurb (approx. $800) or even new one (approx. $1600). If there is a junk yard near, perhaps they have your model on the yard. If yours doesn't have the ASR, I believe you can use one from a sedan too. There is a label on the TB as an aditional measure, match the number and you'll be good to go.

Before anything, you'll have to make sure that your upper engine wiring harness is an updated one. They installed ECO junk prior to 1996 on these models.
There should be a tag in the battery compartment or near, that shows the date of the harness. May take a little searching. Anything before 1996 is most probably junk.
If it doesn't get replaced you may run into more trouble later on, including destruction of electronics devices.

Also, that bare wire from your crank position sensor, should be patched, repaired, since it can dangle and possibly make contact to engine or other ground.

P.S. By ECO junk I mean, powderized wiring insolation or cracked over the length of it. These cracks (exposing bare wire) can short out to other wires and disable your vehicle or destroy other components.
The BIO degradable insolation was installed to safe the planet, unfortunately, the bio degradable insolation degraded before the car did (some of them lasted less than 10 years) and in some case caused serious safety issues.

Have a look at the attachment below, it should match your throttle body...

oldtrucker 01-18-2015 01:36 PM

If your wiring turns out to be the ECO Junk and you get completely lost with the repair of your TB, it can get really difficult with that (the clutch assembly is difficult with the spring, requires some press etc.).
Some people cut the connector housing with a dremel tool to seperate them. The housing itself is a mold type and wasn't meant to be taken apart. Send me a PM. I have a Throttle body from 1996 with good updated wiring e.g. wires that don't fall apart (bench tested) and a spare wiring harness (Delphi) from 2002, for your model.

Just in case you get stuck and need these parts.

244brick 11-01-2015 07:29 PM

Egas computer finally solved it.
I lost that little bar that connects to the throttle lever, does anyone have one laying around by any chance?


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