95 E300D Gauge Issues - PeachParts Mercedes-Benz Forum

vpppmg · #1 06-01-2009, 04:34 PM

Hey everyone, this is my first posting here and it seems like a great forum from what I've read. Thanks for your input in advance!

I just bought my first Mercedes, and she has a few issues. The most pressing being that the gauges aren't working correctly. The fuel gauge bounces rather erratically below 1/4 of a tank, the oil pressure gauge comes and goes (pretty much doesn't function unless you apply a swift slap to the top of the dash) and the speedo is off (cruise set at 60MPH for 1 mile came in at 1min 8 seconds).

It has a new lower engine wiring harness (replaced in November). Any ideas or suggestions?

Thanks.

JimmyL · #2 06-01-2009, 11:14 PM

I'm not sure what might resolve your issues on this particular model. On earlier models a lot of that sounds like a bad ground to the instrument cluster, but luckily I've never had the cluster out of the '95. I guess I'm happy to report that I have no idea because that means I haven't had that issue yet. Lotta help I am, eh?
I just wanted to welcome you to the site mostly. Your answer will come when the right person reads this. The data for this particular model is slowly building up with time. The older stuff has demonstrated their failures far more often, giving us way more experience on those.
Hang with this though, and politely bump the thread tomorrow if still no answers.

TMAllison · #3 06-02-2009, 12:59 AM

I'd have to agree with Jimmy concerning the bad ground at least concerning the fuel gauge.

Doesn't the oil pressure gauge actually have a live feed (eg: a mechanical reading of pressure rather than electronic) from the engine?

The cruise....how did you determine one mile/time? Observing GPS/time vs odometer, observing time/odometer vs mile markers, or other?

vpppmg · #4 06-02-2009, 10:38 AM

Thanks for the welcome Jimmy, I appreciate it. In regards to the grounding how do I go about fixing that?

TMAllison, the oil pressure gauge is mechanical but when the fuel gauge went screwy I thought there might be one central issue.

I set the cruise at 60MPH, went from 1 mile marker on the interstate to another and used a stop-watch. I talked to the owner and he said that the speedo was verified with his GPS to be spot-on so it must have been human error on my part.

Thanks again!

JimmyL · #5 06-02-2009, 02:03 PM

The speedo on my '95 is right on the money per my gps.....
So, I would have thought the '95 oil pressure gauge was electronic.....

vpppmg · #6 06-04-2009, 11:59 AM

I bought a new oil pressure sensor to install as well as oil and new filter kit. Changing the sensor seems pretty straight forward, and I plan on doing it while the oil is drained during the change.

My question is: Is there anything special I need to make sure and do during the sensor change and or oil change?

Thanks in advance!

babymog · #7 06-05-2009, 10:55 AM

Nothing. And you seem to have figured out that the oil pressure gauge is electric, ...

vpppmg · #8 06-05-2009, 10:57 AM

Yeah, I figured that out- thanks. I've had this car a whole week, so...

husk · #9 06-05-2009, 01:01 PM

looks like something is loose behind your cluster, take out the cluster and re attach all cables.....

tankowner · #10 06-05-2009, 02:59 PM

Quote:

Originally Posted by husk

looks like something is loose behind your cluster, take out the cluster and re attach all cables.....

The cluster pulls straigt out. You will need to fashion some tools to do so, I used (as many others have) bent wire coat hangers. Cut two pieces at about 5 inches each, then bed back about 2 inches to make the "handle" and then (in the opposite direction) bend a small segment (about as small as you can - 1/4 inch or so) that will catch the lip of the panel so you can pull it out.

If you are careful you can get these in along the sides (left and right) of the panel and and then rotate the tool so that the small hook end will catch the panel lip as you pull out - you might have to pull hard but it will pop out. Then you can have a look at the wires and go from there. If you need any help with the wiring just ask.

Good luck.

babymog · #11 06-05-2009, 06:48 PM

If the cluster has been out before, you might be able to pull it out with the friction from your fingertips, I usually am successful with this method.

The speedometer cable will stop it as you pull it out. If you have fairly thin arms and long fingers, and are immune to moderate pain, you should be able to un-screw the speedo-cable lockring through the side as you are holding the cluster half-way out.

JimmyL · #12 06-05-2009, 08:22 PM

I haven't removed the cluster from my '95, but I'm guessing it will make it easier if you extend the steering wheel as far towards the driver as it will go.
Also if I have to remove mine I'm thinking of trying the suction cup from my GPS. That is where I attach it when driving and it gets a pretty good grip in the right location....

babymog · #13 06-05-2009, 10:09 PM

You might accidentally tear the lense from the cluster Jimmy.

The pullers are easy to make, cheap to buy.

JimmyL · #14 06-05-2009, 10:48 PM

Quote:

Originally Posted by babymog

You might accidentally tear the lense from the cluster Jimmy.

The pullers are easy to make, cheap to buy.

Duly noted!!

2.5Turbo · #15 06-06-2009, 03:36 AM

I had the same jumpy fuel gauge problem a while back. I put in a few gallons of B99 to try it out and the gauge stopped jumping around. I guess I had a dirty sender and the bio cleaned it out. Might be worth pulling the sender to see if it's gunked.