S70Houston

Starting to find out a few little issues here and there, every day a new experience as I just own this car now for 4 days.

When refueling/pumping gas, the nozzle does not want to stay on the lock position until the tank is full and shuts off every 1 to 2 Gallons. It is pretty annoying and it takes forever to fill this beast up.
Happened to me first when I picked it up on Thursday, thought it was most likely a bad nozzle at an unfamiliar Arco Gas Station.

Today, while pumping gas at a Shell Station near my work the same issue again.

Anyone else experiencing this? Anyone have a fix for this?
Never an issue at any of our other cars????

Thanks very much in advance.

S70Houston

While searching online, I found the following information:

Evaporation Vent Solenoid
One of the most common failures in the emissions system is the vent solenoid. It can stick open, causing the engine control module to think a leak is present, or it can stick closed. A closed vent valve can make refueling difficult as the pressure in the fuel tank isn’t vented. The fuel nozzle will click off constantly, making it tedious and frustrating to fill your fuel tank.

https://www.yourmechanic.com/estimat...id-replacement

Would this most likely be my issue?

OR, possibly the charcoal canister?

https://mbworld.org/forums/s-class-w...-canister.html

dlafever

This was my issue when I first got my car last year. I removed the evaporative unit (because I like to take things apart) and found there to be a foam filter of sorts over the evap vent valve completely clogged with dirt, doing its job. I cleaned the filter and reassembled everything and have had no problems since (28k miles). The whole deal is up under the right rear fender. If the cleaning doesn't fix it, you can get just the vent unit for ~$220 or I think the whole thing can be had for $500. Cleaning was the cheapest.

S70Houston

Thanks very much for this info. OF COURSE I as well like the cheapest solution and would start with the cleaning first.

Could you please be a bit more specific in regards to HOW to remove and WHAT to clean?
- Is this filter easily accessible once the unit is removed?
- Did you also clean the charcoial canister?
- How difficult is it to get to the unit? Just remove the rear passenger wheel as well as plastic fender liner and all is right there? If somewhat mechanically inclined, is it fairly simple, all plug and play?

Thanks so much for any additional information you can provide.

dlafever

You don't have to remove the whole unit.
No cleaning of the canister is practical, that I've seen.

Questions answered in this thread;

https://www.benzworld.org/forums/w22...l-problem.html

S70Houston

SWEET! Thank you so VERY MUCH!!!!!!!!!!!!!! I will attempt this to see if it will fix my problem. Wish me luck.

Beeson

S70Houston

Ghetto or not, if it works it works.
If cleaning the filter is all that is needed, the job does not seem to be too difficult, so I will hopefully get to it myself pretty soon.

The Thomas J

I am dealing with this now. I have to keep the fuel nozzle at the halfway oint so the fuel flows slower. It can be a real PIA to re-fuel. I have noticed some pumps are easier to use than others.

dlafever

Be careful doing this, especially at Costco if you get fuel there. The shutoff valve in the Costco pumps in my area rely on gravity and may not shut off properly if the nozzle is not within a minimum range of deflection. I know this because I watched a dude streeeeetch the hose across the back of his Lexus SUV (need to keep those guys out of our right-handed filling lane anyway!) The only way he could get the hose to fit because he was so far away and on the other side is the turn the fill nozzle upside-down. After his tank was full, he then dumped about 3 gallons of fuel on the ground while I'm blowing my horn and backing up, because he was fiddling with his phone. The attendant shut it off for him and proceeded to spread the evo-spill stuff around the site.

When I got to the pump I noticed it very clearly says NOT to operate the nozzle inverted, and chatting with the attendant confirmed this.

Anyway, be careful please!

Beeson

S70Houston

Could this clogged filter cause the Engine Light to come on?
A couple of weeks ago, right after I got the car, the light came on. I tinkered with the gas cap to ensure it was properly locked and the issue went away, light turned itself off.

Now, approx. 2 weeks later it came on again and I just retightened the gas cap again, light is still on. I cannot remember how long it took last time to reset itself, but I want to say it was not immidiate either.
Does it take a few starts/start cycles for the computer to recycle/reset on the W221, in order for the light to go off?

Should I purchase a new gas cap first, or do you think it is the clogged filter?

Thanks in advance.

dlafever

Truly I think you should see what codes caused the Money Light to come on. Could be entirely unrelated. Usually when I buy a Benz with >100K miles I just plan on replacing a bunch of stuff, like the fuel/air/oil filters, fuel cap, etc. But check those codes!!

S70Houston

Thank you very much. I do agree and thank you for your input.

Unfortunately, this does not answer my question, which was if it was possible for the light to come on due to the clogged filter and fill up issues. Especially since this happened already prior.

Thanks very much.

dlafever

Well, it is conceivable, but I do not know for certain -- which is the reason if it were mine I would go after the codes. I know that a bad fuel cap can prevent the car from passing emissions testing, but also not sure if the engine management system looks at that or even has logic to measure it. At emissions stations it is typically a separate test (they take the cap off and put it on a sucky/blowy device.)

When my filter was clogged, preventing filling of the tank, there was no check engine light or code.

S70Houston

Thanks again.

It is noted on the gas cap, that "a loose cap may turn on Engine Light".

EasyPhil

Should you buy a new gas cap? Did you do a thorough inspection of the one that you have?

S70Houston

I did Phil, and based on my visual inspection it appears to be ok.
I am however wondering if the rubber seal is maybe a bit thin and the cap therefore no longer seals properly/tight. Unfortunately, I have nothing to compare it to.

EasyPhil

You can get a new fuel cap seal: A 168 471 0679

S70Houston

After a fill up this afternoon, and ensuring that the gas cap was tightly secured, the light went off again.

Based on this experience, I would imagine it could only be a bad gas cap or the clogged filter!!!???

S70Houston

Took care of this a couple of days ago and cleaned the filter as well.

This morning during fill up, it pumped approx. 14 Gallons of fuel without shutting off until the tank was full.

Knock on wood, problem seems to be solved.

dlafever

Awesome!

Bklyn

I wish you luck!

S70Houston

Thanks. However, if you scroll down and read all posts, you will see that no more luck is needed, as the fix was successful.