STL-SL500

okay, new owner, didn't know you shouldn't top off on an SL...weird...thought I did all the time with my SLKs...now have the dreaded light shows; bought the new gas cap (by the way, any help how to remove that dot to fasten the new teacher strap to?)

anyway...will it eventually figure itself out or did I affect something else?

i purchased an obd2 reader and have read, downloaded, reset all codes including check engine codes, though, the check gas cap light in red, blinking gas light keeps flashing...anything to do with the evaporator canister? its been raining here for 4 days straight, would that matter? on short trips, all a-okay, but anything longer than 45 minutes, the lights start to activate.

what do you guys think?

this may sound tremendously, and stupidly simple, however, perhaps, should I put some more gas in it and see if the vapors dispel the issue?

ANYTHING other then having to go to the STEALER...

kbob999

You probably overwhelmed the charcoal canister and now have a stuck valve at the canister or the purge valve. You probably need to test with an SDS to find the problem, or start replacing parts.

The purge valve is easy, and under the hood. The canister is at the front of the right rear wheel well, and a little more difficult. If you want to DIY it will cost ~$100 using eBay parts. I think I have a spare purge valve if you want to buy one used.

Search the forums for these items and see what you find for diagnosis and fixes.

moretech

Again we have an important piece of knowledge conveyed by a forum member for people like myself who are newer SL owners and did not know this. I still hope we can get a bunch of these good solutions together in one area of our forum, so helpful in understanding our cars. So much good and needed information for newer owners of SL500's. I'll sure follow this advice.

STL-SL500

okay, so, here is what I did...I DID switch-out the gas cap, as the car is 10 years old and the seal could have been potentially becoming worn. Because we had 4 straight days of chilling rain, I decided to keep driving it, re-checking all of the OBD II messages, clearing them, each time before & after driving, re-securing the gas cap.

I crossed my fingers as I decided to add approximately 7.4+ gallons to the tank (surprisingly bringing the gas gage to right at FULL, though, NO CLICKS. I kept driving the vehicle, checking the messages via the OBD II (not seeing the blinking light or check engine light the last few times), and clearing messages.

Today was a bright & clear day, although, in the 20-30's with windchill.

So far, so good. I am keeping my fingers crossed that whatever needed to unstick, reset, dry out, or otherwise, reconfigure, did so. I had driven well over 90+ miles today, stop-and-go, and it ran like a cherry. I hope whatever issue, remedied itself. I would think, with all of it's superior engineering & testing in the extreme temps, systems can self adjust themselves once they communicate with one another.

So -- take it for what it is...glad I didn't have to throw a bunch of $ into a stupid mistake made by myself.

Lesson to be learned here: DON'T EVER, EVER, EVER, ATTEMPT TO TOP OFF YOUR TANKS!!

mercy-me

STL,

I have been perusing the R230 forums for about 2 years and have never read anywhere that you are not supposed to fill up the fuel tank. I am aware of the loose baffle issue on the early models such as mine but the " DO NOT FILL UP FUEL TANK" issue is new to me and baffling!

Can you please point to the post or article that says not to top up the fuel tank??

Greatly would appreciate it!

Thanks, Bob

STL-SL500

I was just as surprised as you as previously stated, would top-off both of my previous SLK's. However, I'll have to look, but I believe that it does state upon the fueling door not to top off tank; i believe it may mention it as well in the manual. Trust me...you DON'T want to go through what I had...and, potentially, could have..., simply isn't worth the extra few miles...

STL-SL500

I just replied that that I replaced the purge valve under the hood on the driver's side, along with replacement clamp to replace original clamps; thankful for this forum!!

Also -- as my Convenience (systems) battery was dying out every morning (yes, I have a trickle charger however, nowhere to plug it into) was dying-out after approx 6 hours, replaced it, and thought, what the h#@*, did the starter one as well...$675.97 for both (total), and, as it is winter now, and, as the service advisor advised, it NO LONGER IS CONSIDERED going in for an appt but rather the $ amt you spend that you get free M-B roadside assistance, thought I wouldn't chance it since the starter battery was only $288.50 installed (I know, I know, what a rip off), however, when it is the holidays and cold here, I don't want to be left stranded and ONLY a M-B battery supposedly will do. Tell me if I am wrong. In either event -- it is done, the car runs (knock on wood) runs great, and I am confident it will start!

STL-SL500

Status Update - have put on approximately 600 miles; so far so good...so probably was the purge valve under the hood, though, changing out the gas cap probably didn't hurt as well...hope this helps others with the same issue...

STL-SL500

hey mercy me, it's in the inside flap of the gas cap cover along with the user's manual...I just read it in the owner's manual, however, neglected to write down the actual page number. I believe both places are in CAPS & BOLDED.

STL-SL500

thx kbob999 for all of your help! glad i didn't have to get into the charcoal canister's...that would have been pretty costly...i appreciate your input!! thanks for your input!

mercy-me

I see what your are referring to, Pg. 225 in our the owners manual...........



I never top mine out anyway but good to know that it is not recommended in black and white! Mine does not have a sticker on the fuel door, probably fell off!

Thanks,

Bob