• Hi Guest !

    Welcome to the 500Eboard forum.

    Since its founding in late 2008, 500Eboard has become the leading resource on the Internet for all things related to the Mercedes-Benz 500E and E500. In recent years, we have also expanded to include the 400E and E420 models, which are directly related to the 500E/E500.

    We invite you to browse and take advantage of the information and resources here on the site. If you find helpful information, please register for full membership, and you'll find even more resources available. Feel free to ask questions, and make liberal use of the "Search" function to find answers.

    We hope you will become an active contributor to the community!

    Sincerely,
    500Eboard Management

m119 misfire still there after the distributor changed

You are going to remove the valve cover and replace seal (do both sides why not) and the oil separator. May want to review guides and tensioner while you are there. torque specs matter on them, but I bet GSXR will have another thought or two on this, that is not a happy look - arcs.
 
That's a healthy spark... in the wrong place!

Hard to tell what the root cause is without more information. Looks like new (non-resistor) plugs gapped to 1mm are in order, along with a set of plug wires.

If there is liquid oil pooling at the base of the plugs, the valve cover gasket may be leaking - in which case you'll need to replace those too. A small amount of oil residue on the threads is normal.

:run:
 
That's a healthy spark... in the wrong place!

Hard to tell what the root cause is without more information. Looks like new (non-resistor) plugs gapped to 1mm are in order, along with a set of plug wires.

If there is liquid oil pooling at the base of the plugs, the valve cover gasket may be leaking - in which case you'll need to replace those too. A small amount of oil residue on the threads is normal.

:run:
whole plug was lubed in oil lol
 
Hi everyone. I've been registered on this forum for a while and I'm not sure whether I should start a new thread or not. So I'm starting here first.

Two months ago, my 400E w124 wouldn't start after a short stop. It only started after a few attempts. No power and misfiring. I just barely got home. Then I noticed that the distributor caps were quite wet on the inside. So I ordered and installed new caps, distributor rotors (both Bosch) and new camshaft seals. Sparkplugs new. Now the engine starts again, runs good, but when it warms up, the misfiring starts again. The engine wiring harness has been new since last year. I installed new ignition coils today (Bosch). The problem is still there. While idling, I disconnected the hose from the fuel pressure regulator. No gasoline is coming out, so it's fine i think. Driving with the air flow sensor unplugged made no difference. So? What next? Ignition cable? Oh, no errors stored in the error log.

And at least, sorry for my english. I tryed to translate as good as i can 🙈
 
Two months ago, my 400E w124 wouldn't start after a short stop. It only started after a few attempts. No power and misfiring. I just barely got home. Then I noticed that the distributor caps were quite wet on the inside. So I ordered and installed new caps, distributor rotors (both Bosch) and new camshaft seals. Sparkplugs new. Now the engine starts again, runs good, but when it warms up, the misfiring starts again. The engine wiring harness has been new since last year. I installed new ignition coils today (Bosch). The problem is still there. While idling, I disconnected the hose from the fuel pressure regulator. No gasoline is coming out, so it's fine i think. Driving with the air flow sensor unplugged made no difference. So? What next? Ignition cable? O
Sounds like you need to add the additional vent slots to your new caps, AND also eliminate all oil leakage from the exhaust cam seal & intake cam advance magnet/solenoid. Read this thread for details. Very likely this will cure your problem.

:shocking:
 
Hi. Before i installed the new caps i add the vent slots. I will reinstall the old distributor caps and rotors as a test to see if the problem persists. Even new Bosch parts have reportedly been defective in the past. So let's get to work right away. More information to follow later today. An introduction thread will also be posted in the coming days 😉
 

Attachments

  • 20250808_184107.jpg
    20250808_184107.jpg
    1.1 MB · Views: 5
Jesus man... i cleaned up the old rotors und caps and just installed them. The isolation are the new ones. What should i say... it runs fine. The new Bosch parts are bad out of the box... production date 05/18 😐. Im happy that it runs fine now... but, i mean, what a joke... should i install the vent slots in the old caps? What do you think? Behind the Isolation caps its dry like the Sahara dessert.
 
You should still modify the caps with extra slots and go deep on the ones in the bottom even slightly into the outer flimsy plastic.

Yes some of these components are crap out of the box. One thought here is to add the wd40 wipe on everything, including the aluminum housing that we connect up to. In a hot environment, moisture will appear with the humidity (out a cold soda/bear can outside in the summer, use the shade if you want but the can will sweat!) and if there isn't the ability for the atmosphere inside the cap/insulator/rotor and the aluminum and oil vapors along with the other gasses created to adequately escape then you got the funk. New stock by Bosch is showing up with deeper and extra slots out of the box.
 
Jesus man... i cleaned up the old rotors und caps and just installed them. The isolation are the new ones. What should i say... it runs fine. The new Bosch parts are bad out of the box... production date 05/18 😐. Im happy that it runs fine now... but, i mean, what a joke... should i install the vent slots in the old caps? What do you think? Behind the Isolation caps its dry like the Sahara dessert.
Aaaargh! Sorry to hear that. I once had a defective new Bosch cap out of the box, but it "only" caused a misfire on 1 cylinder at hot idle. Sounds like yours is worse. On the bright side, you identified the root cause and fixed the problem. For now, yes, add the vent slots in the old caps. See if you can return/exchange the new Bosch caps.

:tumble:
 
Hi 500E forum

Its been a min since i gave a update i have gotten my 420e detailed cleaned up and as for the car overall its is not running i have changed the MAF sensor which is from a 97 s500 w140 the updated one ill upload a pic down here also i havent changed the coil packs and the ezl what should i change first and what are good adivce on sparkplug wires one more thing what all systems work with ignation to spark plug.

Thank you again
WhatsApp Image 2025-11-27 at 20.28.10_c78b466d.jpg
 
Hi e500 board good news i found a ezl that will maybe come on saturday a local 500e owner reached out and said i have one so he is giving it to me for testing if my car works i will buy it but i want to know if it will work cuz my ezl number is different.
ps the one dusty is mine the other is his

WhatsApp Image 2025-12-03 at 22.34.46_1e93e898.jpgWhatsApp Image 2025-12-03 at 22.34.46_41e93b70.jpg
 
Hi e500 board good news i found a ezl that will maybe come on saturday a local 500e owner reached out and said i have one so he is giving it to me for testing if my car works i will buy it but i want to know if it will work cuz my ezl number is different.
ps the one dusty is mine the other is his
Although you can use any V8 LH module interchangeably, the same does not apply to all EZL's. Certain EZL+engine combinations will NOT work. I am not sure if the early 5.0L EZL will work with your late 4.2L engine. From memory, when I had tested this in the past, the engine either will do weird stuff at idle and/or throw a bunch of fault codes. You really need to test with the correct part number EZL for the car. However, if all 8 cylinders are firing, it's unlikely your EZL is defective.



can i use pc thermal paste on it ?
Yes, but don't bother installing the spare EZL with thermal paste. Lay it on top of your old one, the wires will reach for test purposes.
 
Back
Top