Diagnosing a Failed Emissions Test - High HC, CO and NOx Causes and Repairs

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Күн бұрын

In this video I go over how you can diagnose excessive amounts of Hydro Carbons (HC), Carbon Monoxide (CO) and Nitrogen Oxide (Nox) in your exhaust. I go over how a rich or lean condition can cause one or more of these gases to be high and therefore causing you to fail emissions. Also I go over some components like the Catalytic Converter, Oxygen Sensor (O2), Ignition Coils, Spark Plug Wires, Spark Plugs, EGR Valve, which are part of your emissions systems on your car and how they effect different levels of each gas.
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Disclaimer:
Due to factors beyond the control of Ratchetsand Wrenches, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. Ratchetsand Wrenches assumes no liability for any property or personal damage that may arise from doing a repair on your vehicle after watching any of my repair video's. Due to factors beyond the control of Ratchetsand Wrenches, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Again Any injury, damage or loss that may result from improper use of tools, equipment, or the information contained in this video is the sole responsibility of the user and not Ratchetsand Wrenches.

Пікірлер: 240

@wysetech2000 8 жыл бұрын

I have been an automotive tech for 47+ years and that has to be one of the best exhaust emission explanations I have ever seen anywhere. I just subscribed to your channel.

@myRatchets 8 жыл бұрын

+wysetech2000 Thank you sir, I appreciate your comment and subscription :-)

@ReikoX7 5 жыл бұрын

I am not any atuomotive tech, bu this explanations are great much more easily understandable compared to other stuff that I can find on the internet and all the stuff gives sense.

@kevinllamido9647 6 күн бұрын

@@myRatchets I agree with @wysetch2000 This was excellent, simple and logically explained. and took a lot the guesswork and "randomness" of the suggested fixes. Very consumable. Thank you for taking the time to make this video.

@apuuvah 3 жыл бұрын

Very informative, thanx. Especially liked... 1) If NOx is a pass at idle, but a fail at higher rpm, EGR valve is faulty 2) If NOx is WAY above the limit (2-3x or more) catalytic converter is busted

@carlosk8103 Жыл бұрын

Egr system... Usually EGR is good but dirty very rare for them to fail...

@osielzamora5613 Жыл бұрын

Thank you for your videos, you have a great way of putting all repair in a simple and clear manner. Coming from a person who has 24 year of automotive service . 👍🏽

@johnneszmery5875 7 жыл бұрын

This is the best resource ever!! Using this knowledge, today my 1990 Volvo 240DL with 246K miles passed with flying colors! The mechanic/tester was amazed at the low numbers. I've subscribed and thanks for everything, Man !!

@BellaRocko 8 жыл бұрын

You make excellent informational and DIY videos! It's clear that you have a very good understanding of all auto related functions by how well you can explain them. The only thing that confuses me is why you don't have hundreds of thousands or millions of views and subscribers! Thank you very much for your videos!

@wilsonbent4209 7 жыл бұрын

great video man... the way you explain poor test results to the problem is phenomenal! thank you

@joelmccoin9727 8 жыл бұрын

Excellent Video!!! Very well explained, very clear, helpful & useful. You are a good teacher, Thank you.

@omnidivisible 6 жыл бұрын

Superb presentation. Good thing that I saved my emissions reports. Now I can use the information I learned from you and use the emissions reports to troubleshoot and maintain my car.

@nathanaelnewton6299 5 жыл бұрын

Very clearly explained-It just shows how a good explanation does not require all the other 'how great am I' platforming BS. Well done and thank you.

@johnevon8220 3 жыл бұрын

This is really great information for the consumer, Thank you for your time and effort in putting this all together.

@testplatform582 2 жыл бұрын

Thanks so much for sharing this info. You probably have saved hundreds of people from dishonest repair shops. More power to you Bro!

@Engineer9736 2 жыл бұрын

It’s my issue as well.. car failed emissions test, too much co. I don’t dare to bring it to a garage as i feel like they are going to jack up the price to crazy amounts. Or they break something small on purpose so they hope that i’ll be back later to them. Fixing it DIY prevents all that. Just takes a bit more time and headache…

@meperson 2 жыл бұрын

I had issue with high hydrocarbons on my 1995 Toyota Corolla. I followed your instructions and replaced spark plugs and the problem was solved. Just for a good measure I used engine cleaner, put a new high mileage oil and high quality gasoline. Passed the DQ without any issues. Thank you very much!

@jonnapatricia5191 2 жыл бұрын

It’s a great and reliable video. Was facing this kinda issue back then with my emission test so I had to look for a way, which was how I came across Stray Admin who has got years in experience of helping lots of citizens pass they’re Smog test too.

@jesusgastelum9109 4 жыл бұрын

I never comment or even subscribe. But I subscribed awhile ago. Ever since I was working on my Audi. You've saved me numerous times. Great work sir!!!

@paul-wh1co 5 жыл бұрын

Thank you. This has to be the best explanation for emissions I have ever seen. I also just subscribed

@c.c.8841 11 ай бұрын

thanks for straight answers with no frills, some people are just unable or unwilling to do that and wastes everyones time.

@lanazaakat9466 4 жыл бұрын

Please also keep in mind to use simple language for the common persons who don't have much auto experience and can't find an honest mechanic, especially in these times. . Thanks !! Good Job. I was able to change the timing belt, water pump, all pulleys etc. just by watching your videos and taking notes. !! My 1997 Camry 2.2 L now runs like a charm. I just passed smog. Time, knowledge, and tools are what one needs...Appreciate.

@jag376 Жыл бұрын

I’m sold man. You are way above my pay grade!!!! Thanks and as a diy guy, I appreciated the information.

@TwoCarGaragez 4 жыл бұрын

I always replace everything that’s cheap first. Check for vacuum/air leaks and exhaust leaks. Change your engine oil and oil filter. Change your air intake filter if it looks old. Change the O2 sensors. Add some Lucas fuel cleaner. Check your tire pressure (can make a difference on dyno smogs). Lastly, take it for a 20-30 min highway drive before getting it smogged. Leave it running until it’s tested.

@datadavis 2 жыл бұрын

I did all that. And welded in a new cat. New lambda plug. P.o.s corolla still wont pass for hich co and hc. Now it goes to africa. Bye byeeee! 😂

@patrickdurham8393 3 жыл бұрын

This is an excellent video. Answered so many questions that I had in a way I could understand. Keep it up dude!

@c86tail 4 жыл бұрын

Miss great videos like these from your channel. Very informative.

@Kodo9mm 8 жыл бұрын

Great, full of knowledge, i appreciate you making this video man.

@williamcarpenter79 6 жыл бұрын

Multiple thumbs up mien Doctor! Teaching is your forte, thank you!

@tasadar1695 7 жыл бұрын

you sir have the best video of explaining this, thank you. subscribed.

@rondetorres3842 6 жыл бұрын

Trying to keep MY93 4cl Toyota pick up on the road (work truck). Im pretty versed in "tail pipe" emissions and my "smog #'s) are getting close to not passing. I needed a refresher course on what it takes on my behalf to get my pick up to pass. Thanks for posting!!!

@calvinchou9367 8 жыл бұрын

I had failed my smog test, and after seeing this video I knew what to do. My HC had failed, so I Knew it was the air mixture. I got a new air filter. I also got the "catclean" product...more cleaning. I then removed my negative battery terminal to reset computer. I even got more air in the tires. My HC was 145 when I failed, today it was at 6. Easy pass. Thanks for great video.

@hayypapi4281 4 жыл бұрын

My was 240 and max was 170 what do you think it could be

@sparsa3855 4 жыл бұрын

Hey, Its a practical way of understanding & analyzing the reasons behind failing Emission diagnostic tests, and finding how to deal with to remedy the caused dilemma. thanks for well elaborated & right to point explanation . S. Parsa Feb/2020

@YoDoneSa 8 жыл бұрын

wonderful, I love your videos. There are very good explained and. keep up the good work. good luck from here in The Netherlands

@joseleon2416 5 жыл бұрын

Excellent explanation, excellent. Keep that humble attitude. I did suscribe.

@jamespowton4596 4 жыл бұрын

Excellent insight into high Co + Hc narrowing the component replacement decision markedly.A1

@buyherepayheresanjo 7 жыл бұрын

Great explanation.

@capt251978 6 жыл бұрын

Good job, buddy. Been a tech for 20 years and live in a rural area so... we are not required to perform emissions testing. Trying to get a grasp on it.. thanks.

@wagakamakoyo7309 8 жыл бұрын

I just subscribed man. Excellent videos!

@leonminja7922 8 жыл бұрын

I like the way you explain, I got it clear.

@myRatchets 8 жыл бұрын

+leon minja Glad you like the video, thanks for commenting.

@Engineerboy100 4 жыл бұрын

Good thorough smog prep. review. Thanks. Now I gotta go out and change plugs, clean MAF, run some sea foam through the intake and drive her hard to the smog shop ;)

@barryaugustine1298 3 жыл бұрын

my hc co pass but nox off the charsts 1300 too high so, i changed egr and sensors and got vacuum lines working too distributer ,now im not smoking at idle ,not blowing white smoke i begin too take off ,so now on too cat then muffler thank you sir spot on those problems !!! i recommend getting spark plugs wires firing very very good so you can tell when driving after more power etc..

@richardpotter712 7 жыл бұрын

Very good explanation. One other point is that if you have a thermostat that is stuck open and the engine runs colder than it should, the EMS will over compensate the fuel mixture and the engine will run too rich thus increasing the Co2 levels.

@robbieh1297 3 жыл бұрын

Very good and informative video, well done 👍

@voyage1der449 4 жыл бұрын

Dude thank you so much my 95 civic failed the HC and NoX but just by by a little. My HC was at 0.87 and to pass it has to be 0.80 and my NoX was at 2.60 and to pass it need to be at 2.00 now I know what to look for and try to fix it

@carslover3509 8 жыл бұрын

very very great information i learned to much thanks friend keep the good work

@Tubecraft1 7 жыл бұрын

Thankyou for such a good and thorough vid

@mick2d2 5 жыл бұрын

Thanks for the great explanation.

@user-ru2hf1sg4e 3 жыл бұрын

Great video going for my l1 this helps a lot

@mfable1985 4 жыл бұрын

well taught. i learnt something today! Good video.

@MrForcat 2 жыл бұрын

As others say, best emissions lesson!

@PhilVerryChannel 6 жыл бұрын

Wonderful points. Well said.

@jokjoksson4369 8 жыл бұрын

Great vid! Thanks.

@r.pratherray1364 5 жыл бұрын

So informative! My mechanic and the smog guys have been giving me the run around. After watching this video, I feel armed with useful information that I can take to my mechanic and have my car pass smog.

@ArelSprite 5 ай бұрын

You should be a professor in KZfaq university This was the greatest Emissions video I’ve ever seen

@Molinajme 5 жыл бұрын

Presentation well explained

@eru7774 5 жыл бұрын

Best explanation!!! Thank you!!! Keep it up

@ElizabethDiaz-bi1qy 2 жыл бұрын

Thanks for the video i hope i can get my 95 E420 Benz to pass with this information! I do understand it's an old car and will probably have to make repairs each year but i got a good guide, you.

@ElgarajedeJoseManuelH 7 жыл бұрын

Really goog video. Thank you so much.

@robertohernandez170 8 жыл бұрын

thank you bro very good information.

@nikmamad 6 жыл бұрын

short, put right to the point, Thank you,

@nooretautaya 5 жыл бұрын

Hi. Is there a simple device that could help me test my Co2 emission from my car? What is your opinion about the Carbon Cleaning Decarbonizing..Thanks.

@eluberimabib4070 2 жыл бұрын

Great video

@richardbruce8514 7 жыл бұрын

Thanks that was good info.

@edwinmoreira3370 6 жыл бұрын

I have Toyota t100 1997 need smog

@roontunes 4 жыл бұрын

very helpful thank you

@harlangreen1840 4 жыл бұрын

WORN DISTRIBUTOR CAN CAUSE ISSUES AS WELL...NICE JOB WITH THIS VIDEO

@ericelder2962 2 жыл бұрын

Gr8 info

@eversilva6255 6 жыл бұрын

Thank you for the video excellent

@deanhofmans9667 4 жыл бұрын

Thank you sir. May god richly bless you

@carreteras101 7 жыл бұрын

great explanation. thanks again.

@fishodorvagina 7 жыл бұрын

When I finish my automotive tech school here in Florida, I'm going to California to learn about vehicle emissions to further my education.

@thewolfpackgarage5046 4 жыл бұрын

fishodorvagina did you ever come to California ?

@lukemartin7029 8 жыл бұрын

nice use of the white board!! :)

@nuwangodakandaarachchi8728 4 жыл бұрын

Super stuff

@chriskeiley5343 7 жыл бұрын

this is a pretty good explanation, however it is incomplete. one big thing that most people often over look is carbon build up which can increase cyl pressures and temp's leading to elevated nox emissions, another thing is a rich condition can do the same thing because the cyl pres be higher, along thos same lines is if the head has been machined after a bad warp. on some vehicles i have observed that too much fuel pressure can actually cause high hc's instead of co. every car is different but still a very good video

@redneckkorean303 4 жыл бұрын

Very helpful Can you do a vid on adjusting timing/idle and af mixture on carbureted engine

@huthyfaqahtaan2804 6 жыл бұрын

Thank you for the explanation, I need and advice on that I have removed the ECM from my BMW Z3 1998 and return it back immediately, but I got the engine shaking and vibrating.. is there any explanation to this issue????

@jeffarcher400 Жыл бұрын

Lacquer thinner in the gas is supposed to clean the catalytic converter. It's scary but I put some in my cars and it didn't kill them. It sounded more throaty but can't fix everything. Removing the cat and soaking in solvent is supposed to be the best. My mechanic recommended Seafoam for de carbonizing the engine but then all that goes into the catalytic converter. O2 sensors on eBay are dirt cheap but are they any good? Many plug wires and coils are junk. There's counterfeit products in very real looking packaging. The tip about tire pressure is golden!

@E17AutoServisZadar 7 жыл бұрын

The best explanation ive seen to date. Thanks for your effort.

@IMMU16 8 жыл бұрын

Hi first of all thank you very much for this video i got so much knowledge by this video i always check videos relating to car fix but never seen someone explaining like this . i have one question i drive 1.4 petrol car 3 months back engine warning light came up there was a problem with o2 sensors but i replaced 2 sensors but stll engine light stays on few days later i reset that light but next day engine warning light came back again brought to garage they checked there was a problem with exhaust was leaking they fixed it and last week i brought my car to pass emission test they failed because of high Hc and co and the warning light came back again.so can you please tell me what could be the problem thank you.

@ferdinandwolfpack7561 4 жыл бұрын

Dude thanks

@maxoct7331 6 жыл бұрын

i like the info in this clip and i know its 3 years old but can you shine a light about the the diffrent readings of CO, HC and NOx in relation to each others and what does that indicate. i willing to buy a lexus gs300 the price is less than 2000$ because it failed in the emmesion test because of high CO and not the others is it worth buying and fixing?

@MikeKollin 5 жыл бұрын

Failed smog test. Failed 15 mph test. 100 over PPM at 608. I put new plugs and wires, replaced Head gasket kit 4 months ago. O2 Sensor is fairly new, replaced it 4 years ago on last smog. And also replaced Catalytic converter same time 4 years ago by pro shop that specializes in muffler and Catalytic converters. Had shop rebuild engine 5 years ago. It's really strong engine. Tonight I replaced air filter and put in Guaranteed to pass Fluid. going to replace Fuel Filter tomorrow! Emission test results on fail say: CO2 is 17.4, O2 is 0.0 and again 100 over NO PPM at 608. Any thoughts?

@defons1234 7 жыл бұрын

Thank you very much,great video and explanation, my 1998 Bmw 740il failed smog with high nox at 2500rpm, if you are in california I will ring my car to you.

@thedeathwobblechannel6539 5 жыл бұрын

if you have the original catalytic converter it may need replacing. they do go bad.

@memomunoz2266 4 жыл бұрын

@@thedeathwobblechannel6539 so a car that has the original catalytic converter(about 23 year's old) from 1997 should just be replaced with a new one?

@thedeathwobblechannel6539 4 жыл бұрын

@@memomunoz2266 mine had the honeycomb break apart and would go sideways to the flow and choke off my engine. The "go bad" when the honeycomb breaks. It has no moving parts and no replaceable parts. If it clogs replace it

@jeremiahlyleseditor437 Жыл бұрын

Hey man. Nice Video. It's a big help. I have the opposite issue on the NO failure. High values at idle but normal over 2500. Would it still be the EGR or the relay?

@LuisDiaz-cb3rq 6 жыл бұрын

Great video, I have a 1990 Mazda Truck B2600 2 WD, problems at 25 mph on the NO (PPM) and my truck does not have an EGR. I am working on the solution, any ideas??? Thank you,

@DominicUbble 8 жыл бұрын

I have a 1995 Mercury Mistique with a 2.5 V6. The passages in the plenum behind the gasket of the throttle body were completely clogged and the EGR tube had a split in it so I had multiple things wrong and this caused me to fail the emissions test.

@mansor74 4 жыл бұрын

My 2008 Nissan Altima failed the emission test and were struggled long to find the cause. Ignition coil, Sparkplug, Injectors, MAF, PCV valve, Oxygen sensors, Catalytic converter, Piston rings everything was addressed but the problem still persisted. Finally, someone noticed that the temperature gauge was always showing a very low value. And it was found the thermostat valve was faulty and was stuck open and the ECU was sensing it as cold start condition always and the fuel air ratio was running rich. The fuel economy also improved a lot after replacing the thermostat valve but I miss the sporty acceleration and pick-up when it was running rich. Thought might be useful to someone going through a similar trouble.

@mohamedamer8833 Жыл бұрын

Thanks for the information....Does high oil consumption cause high HC?

@Georgegallowa7 7 жыл бұрын

hi, iv a 2002 jeep Cherokee 2.5 crd sport, my engine blows dark smoke when I sit idle n rev hard. also uses lot fuel. also when driving feels slow under power as if it's been pulled back as you want to go. don't feel right. has it a turbo on it , or some sensor that may cause it to smoke or under powered.

@cantweallgetalong 3 жыл бұрын

I have a 95 jeep g cherokee 4.0 that is passing 15 mph test and failing 25 mph NOX, but no EGR system on this year, any thoughts or direction? 260K and still has good power and acceleration. New CAT fixed 15 mph high NOX, but not 25 mph. Also put a new O2 sensor on 6 months ago to fix rough idle and check engine light. Added new plugs, cap and rotor, but wires still look new. New air cleaner and oil change and coolant is fresh and topped off in radiator. No vacuum leaks detected.

@roberthunker8957 6 жыл бұрын

Over here you get your car back ( a 1976 carbureted 4 cylinder ) didn't pass the Emissions test the problem is that it's undriveable when it did pass. So when you finally did make it home you get a few screw drivers and fiddle around for 2 days so it doesn't use crazy amounts of fuel and runs as it did. No one who bothers you for another 2 years. It probably would have passed in 1976. The only way for it to pass and run as it should is an LPG installation. For new cars guess you covered them all.

@Krillekris 8 жыл бұрын

Love this vid!

@knockout35189 8 жыл бұрын

good info. can you tell me how clogged air filter would affect with high hc or co? The maf sensor is going to measure whatever air comes in through the filter so if a filter is clogged then the maf sensor would just measure whatever the amount of air there is and fuel will be delivered according to that.

@ryanpatton1795 4 жыл бұрын

I calculated my A/F ratio using my ASM results, and im running very lean at 15mph but only a little but lean at 25mph. Would that still be a vacuum leak? I also noticed my o2 is high at 15mph. im thinking maybe at 25mph the vacuum leak is being overcome by something and everything passes at 25mph. can someone please shed some light for me, thank you

@cuttyzonthebeat9634 4 жыл бұрын

I just failed because my Hc levels were to high by 10 and NO was to hogh by 30 im wondering what it can be the smog technician said it wasn't bad at all any thoughts?

@s_l_family9060 Жыл бұрын

Hi i just bought a bmw 116i 2007 just checked its mot and its got (Exhaust carbon monoxide content at idle exceeds manufacturer's specified limits) (Exhaust carbon monoxide content after 2nd fast idle exceeds manufacturer's specified limits). Been to the mechanics changed the nox sensor on it that works fine and the other code was upstream oxygen sensors so the lamba sensor came up if i change that does that fixes it ? And have u got rough idles and less power cant pick up speed that much when the car warms up when the car is currently cold not warmed up it runs and got power to it

@jimmythehood4011 6 жыл бұрын

Every year my 97 Dodge Caravan gets closer to failing the emissions test and this last time it did fail on the HC part of the test, when it measured 62 ppm when it was only allowed a max of 51 ppm. So I decided to try filling it with E85 Ethanol on a almost empty tank and it worked. When I took it back for a retest it drastically reduced the Hydrocarbons (also the CO and NOx) and I passed easily! I recommend anyone who is a borderline fail to give it a try because it worked better than additives and other methods that I tried and didn't work.

@datadavis 2 жыл бұрын

51ppm? Thats insanely low, it would have to run on water vapors, 510ppm more likely? 200ppm is the limit in sweden.

@TheIdiotPlays 6 жыл бұрын

Welp time to checl the O2 sensor and fuel injector... Damn polo y u do dis But thank you. This was helpful.

@bryanespinal7107 7 жыл бұрын

by "A/F" i thought you meant the bulgar abreviation AF loll xD my mind is just dirtier than a catalytic

@tedthomas2753 4 жыл бұрын

My 1994 chevy 1500 MTV have clogged exhaust, I hold a piece of paper at the end of the exhaust and it flaps back and forth help

@aramieg8128 7 жыл бұрын

really good video., I must admit that it takes balls to be in front of a camera and to try to explain all of this info to the general public. Btw you forgot to mention the words "at sea level" 14.7 - 1 ratio at sea level. LOL You have a very confused look. I like how you look and sound like you're guessing. I've been a smog tech since 1990. and I have 2 fancy laminated lists on my shop wall for my customers. #1 If the HC and or NO is slight elevated over the MAX that means you have Carbon build up. Run some injector cleaner through the tank. That's about 300 miles or so for most vehicles. that will clean up the carbon build up. if the CO is elevated replace the O2 sensor. if you have close to or over 200K on the odometer then it's time for the Cat. there are a few different test we can do in the field to check the Cat. with my experience most cars go about 200K before the cat dies. May God rest all of the 9 lives.

@clarencetrinidad9149 3 жыл бұрын

Thanks for making this video. But I have a question about NOx. If I have excessive high NOx at 15mph but lower than avg for 25mpg, can I rule out a bad catalytic coverter?

@JediGokuLee 3 жыл бұрын

Clarence, I thought the same thing for my car (same scenario) but as my CO is very low at both speeds I’m ruling out a bad cat for now and focusing on plugs/wires first (partially focusing on cheaper fixes before hitting the big $$ items). As you commented three months ago and I suspect you had an emissions issue, whatever became of your circumstance? Did you figure out what was wrong?