C43 Problems and Solutions
 

I recently ran into 3 issues that took me awhile searching and piecing together different solutions before I came to the right one so I thought I'd share a couple of my funny problems and the solutions that I finally found. I'm hoping this will make it easier for others to be able to search and find both the problem and solution in the same post. I have a 1998 C43.

1. My ABS/BAS light would come on randomly. If it lit up it was generally soon after I started driving after startup. The solution was the brake light switch that sits under the brake pedal. If you have this problem and you feel like the brake pedal is a little squishy then the brake light switch is probably the issue. As soon as I replaced the brake light switch, I can tell that the brake pedal is firmer and the light doesn't turn on anymore. No special tools needed to change the brake light switch.

2. Once in awhile my C43 would just shut off while waiting at a stop light. When it happens sometimes it starts back up on the first crank and sometimes it would take awhile. Also if I stopped for lunch and 30-60 mins later try to start again it won't start for awhile. I would have to try multiple times before it started. I changed the fuel filter first and that didn't work. The solution was the crank position sensor. You'll need an 8mm torx SOCKET and a few swiveling socket adapters to be able to reach the 1 torx screw that holds the sensor in place. See here

3. When filling up the gas, the fuel pump handle would stop pumping even though the tank isn't filled at all. This seemed to have gotten fixed after I changed the fuel filter. I'll need to test it a few more times and I'll update this after I confirm it.

Hope this helps you all! And if you have other problems with solutions that you can add into a single post please feel free to post it up.

Now this is how you do a thread. Cataloging information for future readers!

I can tell you on number 3:

I've had 3 W202's. They all did that. My 1994 C280 did it for the 13 years I had it. Both my current C43's do it.

My only fix was to pull the nozzle out a little bit and let it fill up. Instead of shoving it in all the way and pulling the handle, I put it in only about 2 inches and let it hang, then pull the handle.

Isn't there something with the charcoal / fuel canister that has to be replaced for #3. I feel like we've been over this issue already!

hi guys

you have to tilt the handle/nozzle if gas stops pumping, sometimes it shuts off by itself randomly then you have to adjust the angle of pump handle gas keeps pumping.
it's an automatic shut off safety device

Regarding no.1 I have had the ABS/BAS light come up randomly on long trips. When I pull over for a short break and then start it up again, it doesn't come up... Weird :/ Only happen 3 times I think.

PS thanks for the tips :)

Yes these problems seem fairly common so I'm sure you've probably been through this before but usually I have to scroll all around a thread to find "possible solutions." I wanted to try and keep it concise so you wouldn't have to search thru each thread to find answers.

As for #3, sometimes it doesn't matter what angle/how far in the nozzle is. The fuel keeps cutting off. I had to basically slowly fill up the gas. But since I changed the fuel filter I don't seem to have the problem. Maybe it was a little clogged and made the pressure build up.

Check this thread out for the fuel nozzle issue: https://mbworld.org/forums/c36-amg-c...al-filter.html

there's a sensor in the gastank when you hit a certain volume of gas, then pump will cut off not to overfill.
replacing fuel filter doesn't have anything to do with the gas-handlegrip nozzle cutting off.

sumetimes pump is cutting off by itself, you have to angle the handlegrip nozzle and squeeze the trigger to pump gas, this is only a safety blocker not to overfill

C43 1999 mysterious problems
 

Hi Kerim,

As this is your first post, welcome aboard this forum.

The symptoms you describe can be caused by several problems: air leak, faulty MAF, clogged fuel filter, etc. My recommendation would be for you to get the vehicle scanned to detect error codes which will point out the faulty area(s) which need to be fixed. IMO this is a starting point which will give you a health report of the condition of your engine and transmission. Better than searching in the dark and investing in parts which may not be necessary.

Keep us informed of your findings.

What's is missing is the airpump used for emission control. If your vehicle is a non N.America version, that's normal you don't have it. Regarding the OBD port, you'll find it in the engine bay at the rear passenger side against the bulkhead. It is not a regular plug and you need a special 30 something pin plug. I may have some photos at home... I'll check when I get back

As DRBC43AMG stated.


https://cimg5.ibsrv.net/gimg/www.mbw...f3840703f9.png
OBDII 38 pin location - NA benz PS engine compartment backside /firewall

Thanks Khomer2 you beat me to it. Ah I see a multiplexer ;) what diagnosis software are you using? Carsoft perhaps? If so it's like mine :D

Just realized that the photo is my vehicle :rolf: Didn't notice until I saw the orange spots on the casing and plug side which I added to make connecting easier :D

Just on a coffee break. Had to clear my mind with all the BS that satellite management has on the other-side of the country.

Yep to carsoft :y

I'll check the codes in a moment when I have access to a larger screen , but I doubt the ECU is shot. I certainly wouldn't fall for that excuse.

Kerim A,
Start by cleaning your MAF with some CRC MAF cleaner (easy procedure). I would also throw in some seafoam as a nice treat for your baby. 2/3 of the bottle thru the brake booster vacuum line (will need a friend to keep the revs up) and do this in the open, well ventilated. Your going to get alot of white smoke and possibly a CEL and a few codes, but these should disappear.
The rest into the gas tank.
I highly recommend your buy yourself a scanner, if you havent done so, as you mentioned you went to a garage. Help you save some money as will need to scan, (in future again).
There's plenty of write-up on these specific topics here on the forum. :)

Have you checked your cats - they may be clogged.
Also what about your plug wires/ ignition coils (last time you swapped them)?
HAve you checked for any vacuum leaks (long shot)?
These codes you produced do point to these potential issues and a few others, but just pointing out what I consider the simplier checks.

You seem to be having trouble in one bank of cylinders 1 to 4 (the left side when facing the engine from the front, or passenger side if you are with a LHD vehicle) and a O sensor also on the left side which could be on the brink. Personally I would clear all the codes so you start with a clean slate and then see which ones come back up to the surface and work from there.

Have you checked all the connectors to the coils and the 8 plugs on the left side? I would also pull a plug from #1 (easiest access) just to see what's the condition on the end.

Regarding a scanner, you first need the 38pin plug (check e-bay) with a Bluetooth adaptor. You can then use an application with your smartphone which will read the codes. To erase simple codes the app will work, but with others you will need a more sophisticated scanner.

I have this one on my smartphone https://torque-bhp.com/ but don't use it any more as I have a more complete diagnostic programme
This is the 38 pin connector with a OBD plug on the other end which you will need: https://www.ebay.com/itm/OBDII-16-Pi...kAAOSwJAtZOD9w
Never mind if it mentions for SPRINTER models, it works perfectly on all the MBs with the 38 pin plug

If you like reading, this is a mine of very interesting info and tech solutions. It was prepared by a member on this MBWorld forum. Goes by the handle MarcusF
https://www.fitzhughmedia.com/MBF/index.html

Keep us informed of your investigations.