The "we" I referred to meant the American public, or at least the vast majority of it who drives. If you read the last of my previous post, you'll see where I alluded to the series of events that begin when people complain, and end with legislation.

The public was growing tired of increasingly complicated automotive systems, all the special tools required to work on them, the manufacturers were keeping information to themselves, and people were complaining. So the government stepped in. They mandated sharing of information (at least for several "critical" systems), and mandated the adoption of standardized trouble codes and nomenclature. They also standardized diagnostic connectors and network protocols allowing one piece of diagnostic equipment to access multiple vehicle lines with very little trouble. This allowed other manufacturers to create cheap "one-size-fits-all" scan tools that allow just about anyone to read out a trouble code.

The trouble is, they never quite got around to mandating that everyone had a solid knowledge of the basic principles of automotive operation. People started scanning vehicles and swapping parts left and right, with some success, and even more "less than spectactular results". And then someone (Al Gore?) invented the internet, and message boards were quick to follow. Now everyone was sharing their lack of knowledge (or lack thereof, as the case may be...) worldwide at incredible speed! Experts were born and destroyed daily, tales of someone's brother-in-law fixing the check engine light in his Jeep by replacing the oxygen sensor spread like wildfire! Everyone had to get in on it, what harm could come of convincing some stranger who you'd never met, who's car you'd never seen, that he needed to buy expensive parts? It's not your money, right? You'll never see this guy. And so it went...

Mind you, I'm not talking solely of do-it-youselfers. There were/are problems across the board. Well meaning friends and family, neighbors, autoparts stores, even (dare i say it?) less than reputable automotive repair shops, even dealerships (I dared). Some steps have been taken to remedy this, some by consumers, who slowly grow wise to the shops that don't know what they're doing, and some by authorities that remind autoparts stores that they are not licensed automotive repair facilities and cannot offer advice as to what parts need replaced (many stores continue to do so, but the state of CA is slowly working to stop them).

But enough of all that. Your concern was with limp mode. "Limp mode" came about as part of OBDII, most specifically, the part where the vehicle's computer had to be able to shutdown cylinders that were misfiring, both to protect the enviroment and the vehicle/occupants. A misfiring cylinder will send raw fuel into the exhaust, which besides being an enviromental problem, can/will cause damage to the catalytic convertor. In particular, it can cause the cat to overheat, reaching temps that can cause the vehicle to actually ignite (this is considered bad for the occupants, as well as the vehicle). Sometimes a disintegrating cat wil spit out chunks or red/white hot material which can start wildfires by the side of the road.

Many manufacturers learned however, that the driving public, who was largely raised with the 70's and 80's "smog-dogs", didn't particularly notice and/or care when a cylinder or two was shut off. Today's cars can run so well with a cylinder or two missing that many never notice. In order to get the consumer to actually stop driving the vehicle and get it fixed, more drastic measure had to be taken. Hence "limp mode". Reduced output, but enough functionality to allow the customer to be able to get safely off of the road, and quite often, to the repair facilty. Sure, there's the odd customer or two who get's his panties all in a ruffle because he can't use his malfunctioning vehicle to, say, tow a boat on vacation, but overall the system works fairly well.

That's about it for limp mode. I'm sorry you haven't been able to find a competent repair shop. Unfortunately, I don't personally know anyone in your area to recommend. I'm not going to tell you that the dealer is the way to go, I see just as many hacks there as anywhere, possibly more, as here in the "real world" we have to survive by actually fixing cars. As a technician in an independent shop, if I don't fix the car, the customer doesn't pay. We haven't any manufacturers warranty to subsidize our shop.

As far as what a guy like me does? Well, I can't say I've never made a mistake, but I've always done everything in my power to make it right in the end. Every vehicle gets a thorough test drive, and the only time they leave with the problem still there is when the customer wants to take them. Bear in mind also that many times people will opt to only fix the immediate problem, by say, replacing the sparkplug wires for only cylinder number 3. It stands to reason, that barring any outside influence (rubbing, rodent snackage...) that if that cylinder's wires are bad, the rest can't be far behind. I understand that it's a lot of money to replace all 12 wires at once, but it sure beats coming back and doing two every two months for two years, especially when you factor in diagnostic time each visit.

I think the guys you're used to dealing with are perhaps a bit more lazy, a bit less skilled, and maybe just a bit unqualified. Some of us are professionals and take pride in our work. But most of you don't care. If a shop offers cheap oil changes and brakes, and maybe throws in a car wash, you're sold. For the record, I'm every bit as disappointed in the lack of skilled technicians in my profession as I am in the lack of people who care enough to seek out those skilled techs.

Oh, and in regards to the rest of your post, the premature failings of EGRs, CPS's, MASS's, those are Mercedes issues. They built the vehicle, I just fix them. Except for the window switch. That was me. All me baby, I f*&ked that one up good just for you.

Any more questions?

MV