Questions tagged [emissions]

The various chemicals emitted in exhaust gasses from an internal combustion engine. The usual gasses which are measured through emissions testing are Nitrogen Oxide (NO2), Carbon Monoxide (CO2), and HydroCarbons (HC).

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Evap. circuit malfunction on Mercedes Benz

I have a 2002 ML320 suv. The CEL is on, and the code is P0446. It states that there is something wrong with the evap. system circuit, specifically at the charcoal canister shut-off valve. I've tried ...
4 votes
1 answer
2k views

High CO Emissions

My Yaris is due for an MOT this month. The last MOT report says that CO is right on the limit, everything else is normal HC, Lambda etc., as shown below. The CO has been creeping up every year, and ...
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Results surprising said lab reporter of emission testing on Toyota Qualis Diesel 4 wheeler on AVL DiTest MDS 205

I got emissions of Toyota Qualis Diesel car tested with the AVL DiTest MDS 205, the result sheet had following columns rpm, temp, secs, CO(%vol.), CO corrected, CO2(% vol.), HC(ppm),HC corrected(ppm),...
3 votes
0 answers
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When will a new emission driving cycle be implemented?

For emssion tests, they have used the NEDC driving cyle here in Europe for quite a while now. I'm not sure about America and Asia, but i believe they use similar driving cycles. After the emission ...
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2 votes
3 answers
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'16 Mazda CX-5 failing HC-PPM emissions test?

I have a 2016 mazda cx-5 with 25K miles that has to go through a yearly inspection. The vehicle's in good shape, plus I take it the mazda dealer for maintenance. I took it to the the inspection center ...
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2 votes
1 answer
2k views

P0491 Secondary Air Injection System Insufficient Flow. Stumped

My VW CC 2010 is having a CEL with the code P0491 which means the pressure sensor is not detecting enough air being pumped from the intake into the exhaust. No other codes. No problems since this is ...
2 votes
0 answers
86 views

Hi CO Emissions - Kial Soul+ 2.0L

My 2012 Kia Soul+ (53,700 miles) failed the emissions test for high HC and high CO at high RPMs (2500). After a new air filter, spark plugs, a professional injector and throttle body cleaning, the ...
2 votes
1 answer
8k views

Check emission system displayed on dashboard display

For the last week it has been extremely cold where I live (varies between -27 to -33 degrees Celcius). Is it possible for a fuel cap check valve to freeze open? Last night leaving work the display ...
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2 votes
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Illusive evap code - Hard to find the issue

98 Honda Civic Ex. For a while now my car will throw a p1456 evap code but sometimes it doesn't and the system completes the test. I'll randomly hook up my obd2 scanner and it'll either have a ...
1 vote
0 answers
72 views

What are the factors that rev hang depend on? Does rev hand depend on the engine load?

I know that rev hangs are intentionally introduced to modern vehicles that operate on electronic throttle bodies, by programming the ecu to close the throttle valve slowly (in gasoline engines) even ...
1 vote
1 answer
88 views

EGR was deleted. Is this the EGR line?

Someone who owned my 1986 3.8l Mustang before me decided to delete the EGR system. I'm attempting to get this car to pass emissions so I want to reinstall the EGR system. However I want to make sure I'...
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1 vote
1 answer
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Emission High CO and High Lambda

It fails at 2500rpm only with CO 0.5~0.6 and Lambda 1.04~1.05. How can it possible be that emission fails because of HIGH CO, and HIGH lambda reading... It means that engine runs rich and lean at the ...
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1 vote
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Inspection Not Ready ( 02, 02 heater, cat)

2006 Ford F150 Battery was unplugged before car was purchased. I bought it and put 300+ miles on it and still see those 3 sensors not ready. No codes. Replace all 02 sensors? Diagnose with mech for ...
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1 vote
2 answers
338 views

MOT emissions fail

My mini 1.4 petrol has failed on high co and hc but only by a small amount . Last year I gave it a service to pass the emissions but this year it’s not having it. I have fully serviced it, added a ...
1 vote
0 answers
45 views

Incereased HC in emission test, low CO VW Jetta 1.4 TSI

Yesterday I took my 2008 VW Jetta (1.4 TSI 122ps with 101k km) for annual emissions test. The car passed the test but I noticed that an increment in HC from year to year, especially when idling (...
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1 vote
1 answer
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CO and Lambda fail after cleaner, air filter and throttle body clean

Went for an MOT, first test failed on high CO AND HC but normal lambda. Got new air filter, cleaned EGR and throttle body and added a cat cleaner into petrol tank. Second MOT failed due to high CO (...
1 vote
0 answers
112 views

Emissions reading on a 1993 Toyota Corona/Carina E 3SFE 2.0

Are these values normal for a 1993 car? If not, please tell me what should be fixed or replaced. I believe it's running rich based on the lambda value.
1 vote
0 answers
25 views

Low idle after adding gasoline

This has happened twice now. My 2000 toyota sienna runs fine until I went to add gasoline. Upon startup, my idle was immediately much lower. I can rev throttle and it sounds smoothly until I release ...
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1 vote
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80 views

2012 Mazda 5: P0422 Code

My 2012 Mazda 5 Grand Touring has been having the following problem. Sometimes it takes an extended amount of time to start and other times it will crank normally, but then sputter and stall. When ...
1 vote
0 answers
89 views

Cannot hold constant RPM on Neutral with accelerator pedal

Having Chrysler Town & Country 2008 with 4.0L gasoline engine. Is it normal that i'm not able to keep engine at 2k RPM for 10 seconds? After some seconds, it just climbs itself up to 3k, but i'm ...
1 vote
1 answer
338 views

Check engine light : code p0455. Idling below 1,000 rpms losing Acceleration power at times and engine dies randomly

Car is a 2009 Chevy impala. Engine code p0455 is the only code my car shows. I have already had a vent solenoid replaced. It was the one by the gas tank that was about a year ago now. No issues ...
1 vote
0 answers
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Does anyone know the OEM for the 2006 Infiniti qx56 oxygen sensors

I've got the part numbers and some cross references for the 2006 Infiniti QX56 oxygen sensors, but I would like to buy from the OEM. Bosch? Denso? infiniti front left/right 226937S000 bosch 17204 5 ...
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1 vote
1 answer
400 views

What could be causing High HC GPM, CO GPM, prevent the RPM from going over 4000, and creating an odd exhaust sound?

I have a Toyota Camry 94, it failed its emission test today with 2.62 HC GPM(Limit is 1.2) , 56.87 CO GPM (Limit is 15). The car also won't rev over 4000 RPM and acts as if it has a governor on when ...
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Car shakes upon startup, dies. Other times gas pedal does not respond

I'm pretty uneducated when it comes cars but im hoping you guys can help me. I have a 99 Ford Ranger that upon startup (not every time) shakes extremely hard and then dies. Other times when driving I ...
0 votes
1 answer
48 views

High HC emissions, CO & NO is ok

I have a 95 Isuzu Rodeo with 3.2. the HC readings are 63 @15mph & 44@ 25mph. I did an oil change, replaced the plugs, wires, 02 sensor, and put in different fuel additives with each gas fill-up. I ...
0 votes
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124 views

High voltage on downstream O2 sensor after driving, but low voltage on idle

After driving on the highway, my downstream O2 sensor voltage was a steady 0.8V, which is high. On the other hand, when idling before the drive, it was a steady 0.3V. Is it normal for the downstream ...
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2012 Automatic Civic firing wrong

I had a question for you all if you'd please help me out. My 2012 automatic civic had its emissions light, VSA light and high temperature lights turn on after I scraped the back rear end on a curb. ...
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138 views

Volkswagen GTI OBDII Readiness

I have a 2015 Volkswagen GTI SE (2.0T) which is (a little over) due for an emissions test. A few weeks ago I had some rear-end bumper damage repaired, and while in the shop they cleared the trouble ...
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Can anyone provide documentation for the 2011 chevy cruze eco grill shutters?

I'm trying to understand how they work and where the motor is since I am unable to get the plastic off the bottom of the grill to access them directly. Mine seem to move if I slowly torque them ...
0 votes
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47 views

Are riding mowers required to have emissions controls in the US?

I know that regular push mowers are not required to have any sort of emissions controls, so mowing is pretty terrible environmentally. Riding mowers are bigger, and burn more gas, so without any sort ...
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