Failed emisons inspection

douglasjreno · Post by **douglasjreno** » 25 Feb 2012, 10:22

So 1994 Volvo 850 non turbo 250K miles, failed emissions for high hydrocarbons limit is 120 failed at 200, what should i check i have no check engine lights, car runs great no missing lags or anything??? Last year it was at 100 now twice as high i have no idea, the state web sites says:
Excessive Hydrocarbons (HC):
High hydrocarbon emissions result when fuel in the engine does not burn completely. HC in the presence of oxides of nitrogen (NOx) and sunlight may form ground-level ozone, a major component of urban smog. Check the following:

Internal Engine Problems
Faulty Air Pump
Ignition System
Exhaust Gas Recirculation System (EGR)
Catalytic Converter
Gas Cap

any help appreciated.

Billc1015 · Post by **Billc1015** » 26 Feb 2012, 10:20

When was the last time you did a tune up (plugs, air filter, cap and rotor, wires, etc)?

douglasjreno · Post by **douglasjreno** » 27 Feb 2012, 10:55

Just did the cap about 2 months ago and the rotor with it. Plugs and wires about 3 years. I am going to do an oil change, air filter and plugs this afternoon, do you think i need the wires as well?

Post by **MoVolvos** » 27 Feb 2012, 13:55

Emissions Failure - High HC
http://www.nichols.nu/tip517.htm

Vacuum Leak

Catalytic Converter

There are many factors contributing to High HC's. A tune up is the first as you are going to do. However, I would look at the above as in very small vacuum leak or catalytic converter not giving code yet can still affect the Smog Test.

My personal experience with this is that due to age of the car you have lower but even compression but sufficient for insufficient fuel burn and the injectors may require cleaning also. I use the following to pass an old $80,000 sticker priced Mercedes in excellent condition which sat for 4 years.

Swepco 306 15-40W to increase compression
http://www.swepcousa.com/lubesite/comments.htm
http://www.pelicanparts.com/catalog/sho ... co_pg8.htm

Swepco 503 clean injectors in one tank and valves to seat better for improved compression
http://www.pelicanparts.com/catalog/sho ... pg9.htm#73

May want to see if you can buy it from a local Porsche or Ferrari Shop. Passed Smog first time at higher thresholds but passed. I would do each step by step so you know what is really causing the problem even though it may cost you a few dollars for each retest. It is worth it.

1) Full Tune Up - USE Copper Core Plugs - May Not Last As Long Though
2) Check Vacuum Leaks
3) Cleaning of Catalytic Converter
4) Swepco last as most people are skeptical

Just passed CA Smog, purchased S70 with 231,000 in Jan with heavy smoke out of exhaust and oil gushing out of dipstick. PCV cleared most smoke and Swepco lessened leak in Turbo. Still some smoke during warm up but after driving the exhaust has no odor what so ever. It also helps to smog in damp and cooler weather.

Blessings,

BKM

douglasjreno · Post by **douglasjreno** » 25 Jun 2012, 20:06

Thanks it ended up being the oil, needing to be changed.

douglasjreno · Post by **douglasjreno** » 24 Aug 2013, 11:32

I eneded up changing the oil and it passed. I have heard that befor that the oil can cause a false failure. So now i change it right before i go there.

Post by **wheelsup** » 25 Aug 2013, 16:27

Cali would freak at my car. I have heater core tubing run from my dipstick tube to underneath the car to vent excessive blowby (PCV system is fine, just overburdened).

Had my car "inspected" in NC, $13.00, passed with flying colors LOL (even after forgetting the dipstick vent)...

FL doesn't even inspect cars, I had it plated there for almost 9 years...

JRobledoVolvo940 · Post by **JRobledoVolvo940** » 22 Feb 2015, 13:33

I just failed the smog inspection in CA. 1994 940 wagon (non-turbo) w/254,000 miles. The part of the test that it failed is the NOx portion at the 15 mph speed but it passed the 25 mph. The max emissions allowed is 556 but i measured 686. The catalytic converter was just replaced 2 years ago, oil changed 2 weeks ago, plugs last done at 237,000 miles and the "check engine" light is not on.

ANY suggestions?

Post by **northernlights** » 25 Feb 2015, 18:27

How old is the O2 sensor? Closed loop operation depends on it working correctly, and as they age the response slows and they loose accuracy. The CEL won't catch the minor degradation due to age that might be causing you to fail.

petek153 · Post by **petek153** » 26 Feb 2015, 09:48

Had trouble with my truck passing and a buddy told me to put a half gallon of denatured alcohol in to a 1/4 tank of gas and run it through. Was a little hesitant but gave it a try ran through without a hitch testing guy asked what I was running for fuel as it did have a funny smell to it lol . Basically it's like running your car on dry gas but cheaper by the gallon.