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Spectacular emissions test failure


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Oh, I'm so proud of Twobaru! If she's gonna do something, she does it BIG! Emissions test yesterday... I was smug, thinking it'd be no problem. Well, the hydrocarbons at cruising speed toasted my dreams of a quick tab renewal. Allowable was 220, we got a glorious 1,058! (idle was no problem, allowable 220, and we got 70) This is with a six month old cat.

 

Went straight to Smart Service, they were suitably impressed by my over-acheiving 96 Legacy. They'll try to find the problem next week. Meanwhile I'm suspecting a thermostat or oxy sensor. Car runs fine, no misfires, no engine lights. Gas mileage sucks (17-19 mpg). I'm thinking maybe the car thinks it's always cold, so dumps lots of gas all the time.

 

What do y'all think?

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what yrs do they do emission checks in your next of the woods?

 

i was told that 97 an newer were the only ones getting checked

 

 

 

nothing like going BIG :banana:

 

In many places all cars are checked, particularly in heavily populated places.

 

I'd suspect the O2 sensor as the ECU should have trimmed that down pretty quickly. does the cat overheat when you are driving the car? You can also check the ECU coolant temp sensor (under the intake manifold, on the passenger side. there are two sensors. the one with two wires is for the ECU, the other one is for the dash guage. Guess which one is harder to get at. . . :brow: ) You may also be getting "blow-by" of oil in the combustion area (worst case scenerio)

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You may also be getting "blow-by" of oil in the combustion area (worst case scenerio)

I've never quite understood why, but the HC test for emissions doesn't see oil. Take if from someone who had a car that was burning a quart every 250 miles and passed! Lesbaru, you're in good hands with Smart Service. There's a low cost option in south Seattle that you can try, but I suspect you have a mechanical problem like an O2 sensor.

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They do a tailpipe test with OBDII vehicles in WA, that's a bit different. Anyway the thermostat and O2 sensor are possibilties. A couple of others are the thermosensor for the ECU of maybe some dirty injectors. For reference my 94 legacy had 13 PPM of HC at 2500rpm, the last time It got tested.

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Cant you get the tank down to just a few gallons and dump a lot of Heet dry gas/alcohol in and make it run clean then?

 

If the results are that bad even this might not work. And with 17 - 19 mpg fixing the problem may pay off with a few more tanks of gas ;-)

 

-Heikki

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Oh, I'm so proud of Twobaru! If she's gonna do something, she does it BIG! Emissions test yesterday... I was smug, thinking it'd be no problem. Well, the hydrocarbons at cruising speed toasted my dreams of a quick tab renewal. Allowable was 220, we got a glorious 1,058! (idle was no problem, allowable 220, and we got 70) This is with a six month old cat.

 

Went straight to Smart Service, they were suitably impressed by my over-acheiving 96 Legacy. They'll try to find the problem next week. Meanwhile I'm suspecting a thermostat or oxy sensor. Car runs fine, no misfires, no engine lights. Gas mileage sucks (17-19 mpg). I'm thinking maybe the car thinks it's always cold, so dumps lots of gas all the time.

 

What do y'all think?

 

My guess would be the O2 sensor. When I bought my 91 Trooper a few years ago it ran great but got 12 mpg and pegged the meter on Hydrocarbons when I tried to get it aircared. I changed the O2 sensor on a suggestion of a friend and I aced emmisions and my mileage jumped to 18 mpg.

 

Cheap fix if it works.

 

Good luck

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