87 300e fails inspection - PeachParts Mercedes-Benz Forum

JEdwards · #1 06-19-2007, 10:47 AM

I semi-knew this was going to happen... when I did the prepurchase emissions test before I bought the car I knew the NOx was close. In fact, the NOx levels failed the the first time and then passed the second time. Quote the mechanic "it has to do w/ the cat, but on a cool day w/ the fan on it if the car is cold you should pass". The problem is there aren't any cool days on the horizon. Its almost July, and cool days won't be available again until sept. This is somewhat of a problem given the fact that I only have 30 days to have the car inspected again (screw emissions anyways). My question is, knowing that the cats for these cars are upwards of 6 bills just for the part, do I have any other options?

I just did a quick search on e-bay and found this :

http://cgi.ebay.com/ebaymotors/Catco-Catalytic-Converter-Mercedes-300E-92-91-90-89-88_W0QQcmdZViewItemQQcategoryZ33629QQihZ001QQitemZ110130600669QQrdZ1QQsspagenameZWD1V

$255 is a lot better than 6 bills, and for that price, I know another mechanic who would install the part, provided I also pay whatever he would have made on the markup.

The NOx levels of this recent test were 3.49 w/ the limit at 3.25. When I did the pretest on a semi hot day 3 weeks ago, w/out the fan on the car, it came out w/ levels of 3.25.

On a side note, since it was Viti that did the inspection I didn't entirely waste my $47, I got a detail, wash, and wax, which makes me pretty happy as well.

david s poole · #2 06-19-2007, 11:10 AM

too much nox usually means that you are running too lean.good trick that i use on a marginal nox pass is to pump up rear tires to 45psi because on the dyno you have two bags on the bottom of the tire not one as on the road and that takes extra power to turn the wheels.

JEdwards · #3 06-19-2007, 03:52 PM

I just went to see the guy who got my Volvo to pass emissions after its NOx levels were too high... sometime at the beginning of next week he said he would play around w/ it and hopefully get it to pass. I'm keeping my fingers crossed that this doesn't involve replacing the cat - I don't like that hefty price tag.

joel · #4 06-20-2007, 10:35 AM

Quote:

Originally Posted by JEdwards

I semi-knew this was going to happen... when I did the prepurchase emissions test before I bought the car I knew the NOx was close. In fact, the NOx levels failed the the first time and then passed the second time. Quote the mechanic "it has to do w/ the cat, but on a cool day w/ the fan on it if the car is cold you should pass". The problem is there aren't any cool days on the horizon. Its almost July, and cool days won't be available again until sept. This is somewhat of a problem given the fact that I only have 30 days to have the car inspected again (screw emissions anyways). My question is, knowing that the cats for these cars are upwards of 6 bills just for the part, do I have any other options?

I just did a quick search on e-bay and found this :

http://cgi.ebay.com/ebaymotors/Catco-Catalytic-Converter-Mercedes-300E-92-91-90-89-88_W0QQcmdZViewItemQQcategoryZ33629QQihZ001QQitemZ110130600669QQrdZ1QQsspagenameZWD1V

$255 is a lot better than 6 bills, and for that price, I know another mechanic who would install the part, provided I also pay whatever he would have made on the markup.

The NOx levels of this recent test were 3.49 w/ the limit at 3.25. When I did the pretest on a semi hot day 3 weeks ago, w/out the fan on the car, it came out w/ levels of 3.25.

On a side note, since it was Viti that did the inspection I didn't entirely waste my $47, I got a detail, wash, and wax, which makes me pretty happy as well.

Do not buy that cat. Bought mine from the same source, and am shipping it back. The cat is loud and it rattles. I suspect the cat's gut is completely destroyed after I pushed my car to the limit. This all happened after one week.

My problem is finding a better cat before I ship it back. Anyone has a source, besides the dealership??

saumil · #5 06-20-2007, 12:29 PM

I just replaced my CAT on a 87, 260E and so far is working great. Got an inspection after the replacement and the emissions are as low as a new car. The brand was CATCO and I paid $255 for it, it was a direct fit and I paid $250 to install it at MIDAS. There are other muffler places that would have installed it for $80 but I think installation is important to not have rattling and other problems in the future.

saumil · #6 06-20-2007, 12:32 PM

Forgot to mention, that it is possible that your problems are not in the CAT as someone has already posted. I changed my CAT because it was completely clogged up and I had no vaccum at idle. Consequently, my RPMs would not go above 2000, a total loss of power is what I had. Also the mileage that this happened was 350K, so these MB cats are quite well built, rule out other mixture adjustment possibilities before changing the CAT.