exhaust gas gurus read this - PeachParts Mercedes-Benz Forum

ducatipaso · #1 07-30-2006, 01:05 AM

the 280TE did not pass the Oregon DEQ (emissions test)
the numbers are:

idle HC: 390
idle CO: 1.6582
idle CO2: 7.3

2,500 RPM HC: 143
2,500 RPM CO: .48
2,500 RPM CO2: 12.8

2nd idle HC: 421
2nd idle CO: 1.2206
2nd idle CO2: 7.7

The HC SHOT up when chopping the throttle after the 2,500 RPM run.
The tech at DEQ said that it's indicative of unburnt fuel coming out the tailpipe.

Any suggestions here? I ran a can of Seafoam thru the tank today just to clean things out in the fuel system. Could this be a sign of leaking injectors?

Anything I can do [ahem, temporarily] to the car to fix these numbers up at the expense of performance (read: timing, EGR) or perhaps just get a new cat?

HELP! I gotta get her registered in OR!

mbdoc · #2 07-31-2006, 10:34 AM

First thing to do is get a letter from Mercedes showing that that car was never imported thru them to the USA...most states will offer an emission exclusion in those cases..I had several euro 280E's & very hard to pass with that high CO readings.. minor mixture adjustment might help...

ducatipaso · #3 07-31-2006, 11:26 AM

Quote:

Originally Posted by M.B.DOC

First thing to do is get a letter from Mercedes showing that that car was never imported thru them to the USA...most states will offer an emission exclusion in those cases..I had several euro 280E's & very hard to pass with that high CO readings.. minor mixture adjustment might help...

Is this letter something I can do through my local dealership? It has a plate in the door jam specifying that it was imported by someone other than MB.

I'm thinking that it needs to be leaned out and detuned just a tad. I'm also going to have a new cat put on it, and put one index hotter plugs in it.

Once it's done, it's good for 2 years.

david s poole · #4 07-31-2006, 01:49 PM

if you will let me know the o2 numbers as well we can establish if lean or rich.generally speaking the co2 needs to be up around 14-15% if running well with good timing and mixture around 14.4 and the o2 should be about .5%.perhaps if you call me i can walk you through it.david poole dallas tx.214-956-7007

ducatipaso · #5 07-31-2006, 02:55 PM

Quote:

Originally Posted by david s poole

if you will let me know the o2 numbers as well we can establish if lean or rich.generally speaking the co2 needs to be up around 14-15% if running well with good timing and mixture around 14.4 and the o2 should be about .5%.perhaps if you call me i can walk you through it.david poole dallas tx.214-956-7007

they dont give you O2 numbers at DEQ unfortunately

Ben12345 · #6 07-31-2006, 04:31 PM

Quote:

Originally Posted by M.B.DOC

I had several euro 280E's & very hard to pass with that high CO readings.. minor mixture adjustment might help...

Over here in England, we are allowed upto 4% CO on a car of that age!

ducatipaso · #7 07-31-2006, 08:29 PM

Quote:

Originally Posted by Ben12345

Over here in England, we are allowed upto 4% CO on a car of that age!

I think that it's crazy that I cannot get some form of waiver or exemption. I drive very little. It's not some smoking beater. I feel sorry for the guys that have rare Alfas or other unique vehicles stored away for weekends. Anything newer than 1975 has to pass the test.

mpolli · #8 08-01-2006, 12:20 PM

I am guessing it doesn't have an O2 sensor?

Mike

ducatipaso · #9 08-01-2006, 02:59 PM

Quote:

Originally Posted by mpolli

I am guessing it doesn't have an O2 sensor?

Mike

It has an O2 sensor and a cat.

curbfeeler · #10 08-01-2006, 03:22 PM

Quote:

Originally Posted by ducatipaso

I think that it's crazy that I cannot get some form of waiver or exemption. I drive very little. It's not some smoking beater. I feel sorry for the guys that have rare Alfas or other unique vehicles stored away for weekends. Anything newer than 1975 has to pass the test.

Here in Pennsylvania if you have antique plates you are exempt from annual inspections and emission testing. The car must be 25 years old and in decent shape to qualify. You submit a request for antique plates, pay a one time fee, get a permanent registration card and thats it. Of course, you still need insurance coverage and not use the car as a daily driver.

ducatipaso · #11 08-02-2006, 01:39 AM

Quote:

Originally Posted by curbfeeler

Here in Pennsylvania if you have antique plates you are exempt from annual inspections and emission testing. The car must be 25 years old and in decent shape to qualify. You submit a request for antique plates, pay a one time fee, get a permanent registration card and thats it. Of course, you still need insurance coverage and not use the car as a daily driver.

I don't know if thats an option here or not but a good call. Thanks for the idea.

ducatipaso · #12 08-02-2006, 01:42 AM

Quote:

Originally Posted by ducatipaso

I don't know if thats an option here or not but a good call. Thanks for the idea.

"This plate is issued to a vehicle that is maintained as a collector’s item and is at least 25 years old at time of application or a vehicle sanctioned as a vehicle of special interest by an established organization that provides for recognition or is a street rod as defined by ORS 801.513. Vehicles may only be used for exhibitions, parades, club activities and similar uses.
Plate Fees: $3 (one plate issued)
Available For: Passenger, motor home, bus, truck, travel trailers, campers, special use trailers, heavy trailers and light trailers"

I wonder if the national MB club would recognize this as a collector's item?

mpolli · #13 08-02-2006, 02:47 PM

Do you have any previous test results as a benchmark? Have you considered trying to fix the problem? Those numbers look pretty bad. O2 sensor could be bad which is not too expensive. Might be easier than trying to work all the loopholes.

Mike

ducatipaso · #14 08-02-2006, 11:36 PM

Quote:

Originally Posted by mpolli

Do you have any previous test results as a benchmark? Have you considered trying to fix the problem? Those numbers look pretty bad. O2 sensor could be bad which is not too expensive. Might be easier than trying to work all the loopholes.

Mike

The numbers on this car have never been stellar. The EGR system on the euro M110 is notoriously undersized.

I'm going to approach this from 3 angles and try again... new exhaust system, new cat, lean it out and try again. I can lick this... it's a solid strong engine that doesn't burn oil.

mpolli · #15 08-03-2006, 02:00 AM

Try the O2 sensor first. And look for vacuum leaks. Don't waste money on a cat unless you are sure that is needed. IMHO. When I had numbers like that (on my Toyota) it was the O2 sensor. It still burns a TON of oil but has good emission numbers.

Mike