MAF HELL. PLEASE HELP!!

As for the puff of smoke after letting off full throttle - it happens. Could just be unburnt fuel being dumped. Worst case, could be oil or coolant. Look at your coolant reservoir; do you have an oily film floating on the water? Are you losing coolant? What about under the oil cap? If you see milky oil residue even after a hard run and the engine is to temp, then that could signify coolant getting into the engine and mixing with oil. If that was the case, your car would be smoking all the time though. I wouldn't be too concerned about that yet.
As for your cats, yes I do believe there are four. There's usually a pre-cat and a cat on each bank. If you're going to replace them, might as well do all four at once and be done with it. If one cat is going bad, chances are the others are on their way south as well. I only suggested replacing the sensors first, because they're cheaper than replacing the cats. And if the sensors are indeed bad, you're still going to get a CEL.
Having them replaced by a muffler shop is easy. Old ones get cut off, replacements get welded back into place. Unless the piping itself is rusted and in bad shape, they shouldn't have to do anything else. Should take less than 2 hours. 6-7 is just nuts. Whoever told you that is just trying to take advantage of an already crappy situation.
Just bear in mind that doing so is tampering with a federally mandated emissions control device. You'd also need to have the ECU retuned since you're essentially straight pipes at this point and the O2 sensors will be giving off false readings resulting in a constant CEL. Not worth the hassle IMO and you'll never pass a smog probe test. Readiness monitors for O2 will also be off - just letting you know in case NYS tests for monitor readiness as well.
When I ran DPF-less and catless straight pipes on my modded TDI, I only did so because my county in PA doesn't perform emissions inspections. However, if I ever wanted to sell or register in another state that does emissions testing, I'd be screwed. Good thing VW bought my car back due to dieselgate.
Last edited by amstel78; Mar 14, 2017 at 09:58 AM.

As for the puff of smoke after letting off full throttle - it happens. Could just be unburnt fuel being dumped. Worst case, could be oil or coolant. Look at your coolant reservoir; do you have an oily film floating on the water? Are you losing coolant? What about under the oil cap? If you see milky oil residue even after a hard run and the engine is to temp, then that could signify coolant getting into the engine and mixing with oil. If that was the case, your car would be smoking all the time though. I wouldn't be too concerned about that yet.
As for your cats, yes I do believe there are four. There's usually a pre-cat and a cat on each bank. If you're going to replace them, might as well do all four at once and be done with it. If one cat is going bad, chances are the others are on their way south as well. I only suggested replacing the sensors first, because they're cheaper than replacing the cats. And if the sensors are indeed bad, you're still going to get a CEL.
Having them replaced by a muffler shop is easy. Old ones get cut off, replacements get welded back into place. Unless the piping itself is rusted and in bad shape, they shouldn't have to do anything else. Should take less than 2 hours. 6-7 is just nuts. Whoever told you that is just trying to take advantage of an already crappy situation.
I actually would like to change the 02 sensors, but no one has seemed to suggest that it's them or that we should at least try them first. I've read mixed things, some say 90% off all efficiency codes are downstream 02 sensors and if it is the cats it's because upstream 02's were bad for a long time. That's why I asked if you were up for a project? Many in this industry run with worse case scenario and if after you've spent big money, you still have a problem, then they want to do small things. It's the reverse order of what financially makes sense. I suppose I can purchase them and go just about anywhere to have them installed. If my cats are indeed shot or on their way out, will this burn out the new sensors though? I don't want to buy them twice and replace cats.
Yes, I am actually curious of what my advisor there would say, as he wasn't in yesterday and I got stuck with the schmuck I dealt with. I watched a youtube video in which it only took 45 minutes, so to say 6-7 hours (at 129/hr) is definitely a "you're a woman, so you're dumb" move.
The Best of Mercedes & AMG
Last edited by amstel78; Mar 15, 2017 at 01:41 PM.
I have searched for ways to rectify this without replacing the cats, I have found everything from a gallon of lacquer thinner to 9 gallons of gas ( yes you heard that right), to spraying carb cleaner into a hole drilled into the exhaust while the car runs, keeping a fire extinguisher handy (sounds like a fun little project, who wants to volunteer).
Then things like cat clean, etc. The muffler shop just called and told me 1800 for both sides
for the Magnaflow. Cant see where they are getting that price, given I found the Magnaflows here http://www.hottexhaust.com/search.ph...2+%22444105%22 185 per front and 165 per rear. They had told me it would only be 2 hours, so Im not certain what they are smoking. Is anyone good at welding? Anyone? I'll buy the parts and the beer
Wish I knew how to weld (and had a 2 post lift in my garage), otherwise I'd help you out.
I came across DEC and they make them, direct fit for my car, just not NY legal. A phone call to R&D and they can and will make them special ordered to fit and be NY complaint. I have to order them through a local distributor and they can have them out in a few days, my guy said he can do direct fit, he cant do the welding. DEC is 950 per cat, 850 if I get my guy to order it through his shop. So presumably around the same as the first shop quoted me to do the magnaflow welds per side. They don't gurantee though and DEC comes with a 2yr/12,000 mile internal warranty and a 5 yr/25,000 mile manufacturer/fit/emissions warranty. I think it may be worth it to go this route.
I was also thinking it may be cheaper to buy an entire wrecked s55 and keep it for my disposal of usable parts
, but this may be a bit much, albeit, possibly cheaper at this point. Any experience with DEC? Any idea if the link I provided are the correct Magnaflow cats?
I wish you did too, I trust you gentleman here a lot more than some of these shops. Knowledge wise, skill wise and the ability to think outside the box here is unprecedented.
Have you called Magnaflow and given them a VIN to cross check their catalog with? You could also ask about their MSRP on the correct cats for your vehicle.
Lastly, have you checked Fleabay? A quick search shows some generic cats and even Magnaflow units for around 120 bucks, and then the DEC units; both left and right for about $500 and change each.
http://www.ebay.com/sch/i.html?_from...5+amg&_sacat=0
Last edited by amstel78; Mar 15, 2017 at 10:45 PM.
Have you called Magnaflow and given them a VIN to cross check their catalog with? You could also ask about their MSRP on the correct cats for your vehicle.
Lastly, have you checked Fleabay? A quick search shows some generic cats and even Magnaflow units for around 120 bucks, and then the DEC units; both left and right for about $500 and change each.
http://www.ebay.com/sch/i.html?_from...5+amg&_sacat=0
Yes I did check out eBay, the dec ones you see there are the ones they make for my car, a direct fit, but they are not CA/NY CARB compliant. They are willing to custom make them NY CARB complaint, direct fit for 950 my cost/ 850 if my guy orders them through his shop.
So now it's just a matter of which is the best way to go. Cut and weld 4 brand new cats for around 850 total (have to call around and see what local shops will charge just for installation) or direct fit one for about 1000 (my guy won't charge me much, but I'll have to give him something. What are your thoughts on the matter? Does it matter either way?
http://www.dec.ny.gov/chemical/90781.html
Per the regulation, as long as you use a certified AMCC (after market cat converter), you should be fine. I didn't see anything there stating it has to be NYS compliant, just that it has to be a 50 state certified aftermarket unit. You should ask DEC if they're 50 state carb compliant, which they should be since they're new units.
My thoughts? Go with the cheapest legal option available if a cat replacement is indeed warranted.
you can probably get the entire exhaust system front to rear including o2 sensors for $200
try these , although I think they are selling the whole cars
https://newyork.craigslist.org/que/cto/5982350826.html
https://hudsonvalley.craigslist.org/cto/5965152843.html
https://newyork.craigslist.org/que/ptd/6017664849.html
Last edited by tusabes; Mar 16, 2017 at 01:05 AM.
you can probably get the entire exhaust system front to rear including o2 sensors for $200
try these , although I think they are selling the whole cars
https://newyork.craigslist.org/que/cto/5982350826.html
https://hudsonvalley.craigslist.org/cto/5965152843.html
https://newyork.craigslist.org/que/ptd/6017664849.html
A search I did several days ago told me that my s55 cats were not the same as the s500 or s430 cats. Mercedes only charges $470 for the s500 cat where mine are 2100 or some other foolishness.
Are they intact interchangeable?
I decided to shop around and came across a custom exhaust shop that had good reviews for being honest, fairly priced and doing good work. He said even though I have 4, the rear two aren't being read by the computer, so there is no sense in replacing them. He said if it were his car he would replace the front 2, eliminate the rear and straight pipe it. He said if he were to get them it would be 429/per side plus 95/per side for the rear, a total of 1049. I told him that I had found the magnaflow fronts online for $185/ea with 25% off- 138/per cat, 277 total. He checked they were the correct ones and told me to buy them and he'd weld fit them for $175/per side, plus the $95 per side to eliminate and straight pipe the rears. So a total of $540 for him to install, $277 for both cats- $817 in total.
I think this is a good way to go. This way they are both done and I don't have to worry about doing the other a month or two down the road. I believe his price is fair, not much to compare it to though.
The above link mentioned catalytic converters, but after reading the first paragraph, hilarity followed. Just thought I'd post it to brighten your mood. Enjoy.
According to the exhaust guy, the downstream sensors are directly after the first cat. I asked him if spacers or any other adjustments would be necessary for the 02 sensors with the magnaflow cats and he told me no.
I thought the price sounded reasonable, being that I have heard the front cats are a real PITA to get to.
I certainly hope this is it as well, I'd like to spend more time enjoying the car. It's been quite a complex project thus far.
So I reset the code and borrowd a pocket scanner from my guy to watch readiness monitors. Code came back 3 days later (yesterday) before last 2 monitors were ready.
Here is the freeze frame data and I am hoping you gentleman can help me interpret what I am seeing.
https://*******/photos/QPrHVFt1xLkuN9Xa8
Last edited by CLK500 TWINS; Mar 22, 2017 at 01:44 PM.







