Gman91932

I tried to pass smog on my perfectly running 300e. IT DID NOT, It was suggestred to get a new oxygen sensor and a new catalytic converter. Wel my trusted local service station decided to try adjusting the oxygen sensor but that did not work. He then suggested a chemical to ad to the car to clean the carbon out of the engine. Well that worked but now my car runs like ****!!!!!!
help!!!!!
Gman

soldsep

i had same problem they adjust retard on my car so it would pass now its slow. sigh.

Gman91932

what to do? any suggestions, took it back to my normal mechanic and he doesnt know what to do either...

Gman91932

When I went back the mechanic adjusted the Idle. Now the car runs a little smoother whiule driving BUT..... at cold start it will not stay started and at stop lights and sighns it wants to cut off. This is even worse then it just feeling rough, now it wont stay started.
Gman

soldsep

time for new mechanic.

Gman91932

The mechanic spent two days on this car and its is back to normal.
he adjusted the linkage? and richned it as well as adjuted the idle. IT still has a little intermittent"hesitation" at a long stop light or stuck in traffic. Like a kind of a "hiccup" Dont know what that is, if anyone has info let me know.this was like this before smogging. This car has about 250,000 mile or so.


Gman

soldsep

wow 250000 miles craaazzy. im only at 175000. and i still need to figure out how to bring my car back to normal.

pifcat2

I had to smog my '86 that had 275k. The smog station mechanic said it needed a cat converter and O2 sensor so I took his word on it and got an aftermarket converter (cheaper @ $350 installed). Well it didn't pass and he said it was just his "suggestion". I believe the converter was good and the O2 sensor was the (less expensive @ $40) culprit. This was a Bosch equivalent that I had to solder to the stock plug. Anyway, this did the trick and the emissions passed. If you really need a converter, make sure you order the dual inlets and dual outlets type.

wby300

The main problem that these mechanic are not understanding is that the Cats used on MB's are so well disigned for the standard operating temps. So many people get nailed with this when it comes time to smog there MB's.

The reason they say the Cat needs to be replaced is because in order for the MB Cats to work they have to be super hot, as if you are driver on the road, and people come into smog shop most of the time the cars are shut off or left that ideal intill the mechanic is ready to smog the car, this lets the Cat cool and not operate well, so the fix to many of these Cat rip-offs is to run the car at about 2000-2700 RPM before the smog, so the Cats work like they are made too.

Gman91932

The problem with my car WAS that there was ONE bad spark plug wire! Now when I went to a diferent Mechanic he saw the problem and changed "the end" of the wire and not the whole wire. He says that spark plug wire NEVER go bad on Mercedes and has only EVER changed the ends. Now my car runs great (knock on wood) and the trip to a differnt or same mchanic twice a week is finally OVER!!!!!

Gman
:p

pifcat2

Gman91932
Why don't you post the place where you got bad service and the place you got good service so that others know who to avoid and where to go? Mechanics that can diagnose the exact problem quickly and give a cost effective fix are very rare.