I took my 1993 190E 2.6 to a Gold Shield Station as per my registration renewal form today and could use a little bit of help with the test results.

15 mph @ 1754 rpm- co2 14.9, o2 0.00, HC (PPM) max 86, Avg. 21 Meas 97, CO% 0.5 max, 0.06 avg, 0.06 Meas, NO (PPM) 697 max, 150 avg, 150 Meas. FAILED (HC)

25 mph @ 1725 rpm- co2 14.9, o2 0.00, HC (PPM) max 51, Avg. 13 Meas 51, CO% 0.48max, 0.06 avg, 0.02 Meas, NO (PPM) 724 max, 136 avg, 83 Meas. PASSED (but barely on the HC) .

Before the test I had changed the plugs (Bosch non-resistor H9DCO) and air filter , the has had an oil and filter change within 1000 miles. Prior to arriving at the test station, I took it on a drive and the freeway about 20 minutes and 25 minutes back down, the car was running about 82 degrees on the temp gauge.

I've never had a car fail smog before and wonder if there is anything else I should have done, or can do before my free re-test.

Thanks in advance.
David

__________________
1993 190E 2.6 135k
1989 Ford Thunderbird SC 5 Spd 79K

CHANGE THE OIL! Make sure you have a new gas cap too. If they don't look for an air filter take it off. I had to replace my Cat to make my 380SE pass, but I bought an anfter market one that was a high flow design. You don't say how many miles on the car. I also did a complete tune up before, Dist. Cap, rotor, and brand new Beru Wires($$$OUCH!), new gas cap, I ad a new air filter and a new filter for the airpump(in the air cleaner box on the 380SE). Mine had 184,000 miles on the original CAT. so it was time.

With the engine that lean..CO 0.06%, the HC's are at their limit.
A slight mixture adjustment (richer) MIGHT allow the HC's to drop.

Secondary ignition needs to be "perfect"

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator

A little birdie said something about some denatured alcohol...

__________________
1991 560 SEC AMG, 199k <---- 300 hp 10:1 ECE euro HV ...

1995 E 420, 170k "The Red Plum" (sold)

2015 BMW 535i xdrive awd Stage 1 DINAN, 6k, <----364 hp

1967 Mercury Cougar, 49k

2013 Jaguar XF, 20k <----340 hp Supercharged, All Wheel Drive (sold)

The car hit 147K today, the tech did not remove the air filter cover and the oil and filter have 1k on them. They did remove the gas cap and put it on a tester ...it passed fine. My father was the previous owner and replaced the Cat a couple of years ago, don't really know if its OEM or aftermarket he just said it was expensive.

__________________
1993 190E 2.6 135k
1989 Ford Thunderbird SC 5 Spd 79K

Did the little "birdie" happen to mention how much of a mix ? I'm at 3/4 of a tank right now.

__________________
1993 190E 2.6 135k
1989 Ford Thunderbird SC 5 Spd 79K

I think the mix was a gallon to every like 5..... Let me check on that though.

__________________
-Justin

91 560 SEC AMG - other dogs dd
01 Honda S2000 - dogs dd
07 MB ML320 CDI - dd
16 Lexus IS250 - wifes dd

it's automatic.

Thanks,
If it is any where near that rich of a mix , I think I should run the tank down a bit before adding any. Then I can dilute the mix with gasoline. I don't know if a 1:5 alcohol - gas mix would be a good thing for a near full tank.

__________________
1993 190E 2.6 135k
1989 Ford Thunderbird SC 5 Spd 79K

If someone was to put some denatured alcohol in the tank in an attempt to pass smog...is there a specific type or grade that should be used? Also ..who sells the correct type /grade denatured alcohol for this test?

Thanks
David

__________________
1993 190E 2.6 135k
1989 Ford Thunderbird SC 5 Spd 79K

I just changed my oil (to 15/50 from 10/30) and filter. I'm a bit over a 1/4 tank (last time it was full) and ready to add some denatured alcohol. How much should I add to approx. 5 gallons of premium?

Also is there any risk to the rubber seals with this trick? I will top off the tank right after the test.

Thanks in advance,
David

__________________
1993 190E 2.6 135k
1989 Ford Thunderbird SC 5 Spd 79K

Hi David,
I had the same problem on my 190e after many adjustments and mechanic tweaking it turned out all that was keeping me from passing emissions was because I had changed my spark plugs to Bosch Platinums once I put new standard spec copper bosch plugs in I passed by a huge margin.

If it was me I would trust the guy with 6 lines of credentials and 38 years experience.

__________________
1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra

Please don't get me wrong.. I know any tricks I may use won't fix the problem. I only have two days to get a pass on my free re-test and the parts I have ordered will not be here until next week.

"6 lines of credentials and 38 years experience" more than works for me. I have a cap, rotor, ignition wires, 02 sensor and air filter in transit and intend on installing on arrival. Messing with the fuel / air mixture makes me a bit nervous though.

__________________
1993 190E 2.6 135k
1989 Ford Thunderbird SC 5 Spd 79K

YES!!!! Dump in a bottle of "Guaranteed to pass" Methanol mixture and drive it until this tank is empty, then refill and go back for your second test and you should pass!

Been there and done that!

you are a bit lean. but many times on a reading like that it indicates a failing
catalytic converter. have the front ones checked.