When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Well, I guess I should have moved on this faster. Today I was driving out of the city to the village where the in-laws live. Two lane road, speed about 50 MPH but many do 60 MPH.
I started to pass an 18-wheeler and as I stepped on the gas to accelerate hard I felt no power and saw no increase in RPM. As I was doing this the Check Engine Light started flashing until it became solid. Temperature was normal if not low. Car ran ok in the 50 to 55 MPH range. Just felt like it could not accelerate well.
I got where I was going and left 30 minutes later. It seemed like it ran ok, even acceleration above 50 MPH. However, the Check Engine Light remains.
Off to exhaust place first thing in the morning. Hopefully they can unclog it and that's it. We'll see.
I would not rely on a muffler shop to nail your Mercedes check engine light.... it's above their skill set. Find a local Mercedes specialist is a better move.
Also beware about arc welding on cars... a good friend of mine with a BMW-Mini got a fried ECU after welding his muffler at the muffler shop recommended by local BMW dealer in Marin County, CA.
Last edited by CaliBenzDriver; Dec 20, 2024 at 02:48 PM.
I would not rely on a muffler shop to nail your Mercedes check engine light.... it's above their skill set. Find a local Mercedes specialist is a better move.
Also beware about arc welding on cars... a good friend of mine with a BMW-Mini got a fried ECU after welding his muffler at the muffler shop recommended by local BMW dealer in Marin County, CA.
Thanks for the heads up. I just want the exhaust place to clean out the catalytic converter, if that's the issue. I will be going back to the electronics shop that fixed my front and rear SAM's for the CEL. (Was going there anyway for the rear defroster, I think I need a relay.)
The local Mercedes Specialist doesn't do exhaust for some reason, and sadly could not recommend anyone despite their 35 years in business here. They just told me to take it to an exhaust place. Only other move here is to go to the authorized dealership.
I found a place with pretty good google reviews. People here keep a lot of older cars running, and can be pretty careful with their money. I think the average age of cars on the road here is 12 years compared to 5 years in other major Western cities.
I hit the muffler shop first thing this morning. At first there was no rattle in the cats. He almost sent me away. Then after running the car we heard it loud and clear.
He said he did not have cats for it but he could put in a pipe (2 pipes actually). He said I should still pass emissions because these are secondary cats and the primary ones are just behind the engine. So he did it and the car seems to certainly run better.
I am still worried about emissions so I saved the removed cats in case it doesn't pass and I haven't figured out another solution by October. We can always put the rattlers back on. The place actually did official inspections in the next bay but told me there was no way to "test" as all numbers are routed to the government.
I was encouraged by this UK post on another site from 2007. Still trying to find the limits here where I live:
================================================== ============================== I thought this may be of interest to someone. My CLK320 has four cats; two 'pre-cats' just after the manifolds, two further cats roughly half way along the car. A while ago, the rear cats started to rattle, indicating they had broken up (a common problem). I'd read on here and elsewhere that you 'may' be ok on emissions with only the front cats in place, but couldn't find anything conclusive. After discovering the VERY high cost of the cats on a CLK (£800 approx from MB), I decided to see if the emissions were indeed ok with only two cats. A friend of mine removed the exhaust, made neat cuts in the top of the cats, emptied them, and welded them back up. I instantly noticed how much smoother the engine now performed, even the gearchanges are smoother too.
However, today was MOT day, so time to test the theory!
Anyhow, good news, it not only passed the emissions test, it absolutely breezed through!
Results per test sheet:
Fast idle - CO:- Limit 0.20%, result 0.00% HC:- Limit 200ppm, result 5ppm Lambda limit 0.97 - 1.03, result 1.005
Natural idle - CO:- Limit 0.30%, result 0.01%
================================================== =============
My CEL remains on. We made no attempt to clear it. Please correct me if I am wrong, but are all the relevant sensors around the first two cats immediately behind the engine? That's what it looks like from this picture I pulled off the web. Are there any more sensors behind it? If there aren't why did I get a CEL? I am hoping the light came on when one of them clogged momentarily and someone can clear it now and it stays off.
Much discussion in this W208 thread, but it goes further into removing resonators. I doubt the two secondary cats on my car were producing any significant back pressure. https://mbworld.org/forums/clk-class...t-removal.html
Back to the electronics shop this week I hope for the CEL and Rear Defroster.
I got an early Festivus (It's tomorrow the 23rd) Miracle late today. My Check Engine Light (CEL) went off on its own. I will still see if there is any record of it later this week.
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.
