Emissions testing

[Wordensong]

My wife's 190E 2.6 failed the idle portion of the Delaware state emissions test. Today I replaced the plugs and cleaned the air filter. It appears that the main ignition wire has been arcing, but this has not been replaced yet.

She passed the high speed portion of the emissions test OK.

The car emits a small blue puff from the tailpipe when starting --- valve seal wear? Car has ~115,000 miles on it.

Anything a fairly adept individual can do to improve low rev emissions?

Thanks to all. (What a great site! I just used the 'reset check engine light' posting to clear the indicator on my E320S.)

Blessings and prosperity,

--s--

Stephen W. Worden

[chowpit]

What part of the idle test did the car fail? HC, CO?

[Wordensong]

Both HC and CO failed at low speed.

HC------------IDLE----HIGH SPEED
READING--612-----201
LIMIT---------220-----220
RESULT----FAIL----PASS

CO------------IDLE----HIGH SPEED
READING--1.36----0.50
LIMIT---------1.20----1.20
RESULT----FAIL----PASS

CO+CO2---14.1----14.9
O2------------0.0-----0.0

Thanks for the help.

--s--

[Edited by Wordensong on 04-19-2001 at 11:14 PM]

[Wordensong]

Anyone have any ideas on this, or are there too many possibilities? Time to take it to the shop?

Thanks,

--s--

[420SEL]

I had trouble passing in Ontario Canada last year. Hydrocarbons were high 170 against a 103 pass (wish I lived where you do). They made some lambda adjustments, replaced the plugs and then did a motorvac. I passed at 102 against a 103 limit. I really really hate emissions testing. As far as I am concerned my car hasn't run as well since they made those changes. Fortunately my car will be 20 years old in 4 short years and will be exempt from emissions testing here. From now on I only buy 20 year old cars.

[David C Klasse]

Wordensong,
I found this webpage and thought of this thread. I hope this helps!!

http://www.mbz.org/articles/misc/emit.html

[stevebfl]

I looked at this last night and I guess I was too tired. Its really very hard for me to answer this question as the simple first step is beyond most every one asking this question.

There is NO way that car would fail those standards without severe failure of the feedback control system (and catalytic action as a result). Since the first step is to monitor that system its very hard to give advice.

Since its unlikely that a real diagnostic can be done at home, my advice would be to replace the O2 sensor (if 115,000 miles old). If there is a misfire at idle I would replace all the plug wire ends. I would do this because its not bad maintenance and might grab the problem. I wouldn't waste any other funds till the system can be evaluated. If you want to evaluate the system view the article in the DIY section and ask any questions that come up.

[Wordensong]

Took the shotgun approach.

Replaced the rotor, cap, wires, spark plugs, changed the oil, upped the idle speed slightly (~850), and filled the tank with Sunoco 260 or whatever it is.

Boom. Big difference, HUGE difference.

Before and after. (Note the AFTER rows.)

HC------------IDLE----HIGH SPEED
READING--612-----201
AFTER--------20-------39 <<<<<
LIMIT---------220-----220
RESULT----FAIL----PASS

CO------------IDLE----HIGH SPEED
READING--1.36----0.50
AFTER------00.0----0.03 <<<<<
LIMIT---------1.20----1.20
RESULT----FAIL----PASS

CO+CO2---14.1----14.9
O2------------0.0-----0.0

Thanks for the previous reply, David.

All the best, everyone,

--s--

Stephen W. Worden