The live demonstration, in particular, accompanied by interpretive commentary, is invaluable. Thanks for taking the time, and for communicating clearly.

That dog analogy is spot on and is such a great way to explain STFT and LTFT. Well done!

AMD is a great Human being for us all. God bless this man and his family and all the success they deserve 🙏🏼

I have always wanted to see someone explain these values in "real time" etc. Great explanation, and I don't even own a Toyota

Ahmed. Wow! I had to watch this one twice. Amazing all the things happening when we run our vehicles. Also amazing how you are able to look at the data to diagnose issues and what the numbers mean. Its great that you explain how all of this work. Thank You.

I'm a musician and like automotive diagnostics, how things work can, and typically do, get far more complicated than they needs to be . Thanks for "dumbing it down".... it really helps me to understand the premise you are teaching ... this is a great series and you've helped greatly in my understanding of the workings of my Toyota and car diag. in general.... ps.... love your analogies... they're spot on. Many auto diag teachers either leave out key info or steer their info for professional techs leaving us novices in worse shape than before... appreciative in Idaho

If only everyone was a teacher at heart like you are sir, this world would be a better place.

This is actually great information because I feel like one of my cars has a leaking injector but it's not throwing up any codes and the car runs perfectly fine. I can use those techniques you just taught me to check if one of them is actually leaking. As I said in one of my previous posts I'm a mechanic but I specialize more in suspension work. And I don't just deal with Toyota's I deal with all kinds of cars. This is why I love your channel because you go into detail on things that I can learn use to better diagnose issues.

I'm supure amazed by how you bring your explanation to everyone ones level of understanding.... I honestly don't know how i vane across your channel but I'm very grateful for coming across your channel and meeting a well educated and full knowledgeable technician like you... You're role model to the car repair industry ❤❤❤❤

HI, AGAIN I LEARNED HOW HELPFUL THE TOYOTA SCAN TOOL IN ITS ABILITY TO ENRICH AND LEAN OUT. NOBODY HAS SUCH INFORMATION THAT VALUABLE ON ANY STUDY CASE. THE DATA YOU SHOWED US IS AS CLEAR AS THE SUN LIGHT. KEEP UP THE GOOD WORK. THANKS A MILLION, MAY GOD PROTECT AND KEEP YOU.

I have watched many videos wanting to learn about fuel trim and all the same, but this video is long but with a better explanation of various situations and scenarios. thanks and thumbs up.👍

Good that I found this video! On my 2010 Acura, LTFT is about +2.5 and STFT is +5/6 and it seemed that system was adding a bit of fuel which indicate a "lean condition". After listening to what you have said "this isn't an issue at all as system is able to compensate..." Just wanted to improve MPG a bit, but I guess I will let it slide and have a better sleep at night :)

Thank you for the amazing videos! These video has definitely reduced troubleshooting time for my DYI work and increase the longevity of my FR-S and 2 Scion tCs. Keep up the great content.

Thank you again for the information! I knew some things, but now they are much more clear.

These are the best videos as it shares your years of experience with us DIY mechanics that don't fix our fuel systems everyday. Thanks again!

Thank you for this video! I had to rewatch the video a few times to get a good understanding, but I was able to find and fix the issue in my 2007 lexus is250 and learned a lot of useful information for future diagnosis. No more check engine light, plus my my LTFT went from 26% to 1% after issue resolved and I'm happy with my fuel efficiency now. You're the best man keep doing what you're doing!

Learning more about fuel trims. Thank you. Between you and scanner danner and schrodingers box I might get it. Glad you said the part about not having ltft at zero. I guess some people are just lucky to have perfect engines and conditions.

Thanks AMD for making these videos. I've always wanted to know how to interpret the readings of my Autel scan tool (other than read and erase codes). After watching your videos, I am starting to understand the data and the reason for them. Please keep up the good work. May the Lord bless you and keep you safe.

I like to watch diagnostic vids for curiosity and always see these charts and never knew how it worked now it feels like i put on glasses 🤓 because i was blind. Thanks for teaching this stuff.

Thanks for another EXCELLENT video & explaining the Long and Short trim levels. After viewing and listening to your analogy, I am fairly certain that it would be a lot less confusing (and not even require an analogy) if Toyota had called short term trim something more accurate like "real time trim data". Same goes for long term trim which, in my opinion. would be MUCH more easily understood if it was referred to as "rolling average trim data".

Excellent - So glad you exist and want to share your knowledge! I was a mechanic in the late 60's to the late 90's - my have things changed! You are a lifesaver! Thank-you.

Not only have you taught me hiw to actually look at fule trims, but you alleviated some concerns. Thanks!

I love the way you explain the technical aspect of engines, parts nd how they work! Great Channel, my friend! I watch all of your videos. I was a mechanic for 37 years on my Dads Tree farm. But now retired and do Mobile Mechanic Service! Thanks for the great info! You are very taltented!

This is the best explanation of STFT and LTFT I have ever seen!! Bar none.

Thanks for the great explanation of engine tests. I am no longer clueless, just old.

Fuel trims can throw you. For example. Watch when your LFT reads 12.5 and your SFT reads -10.5. This can confuse people, but actually, your TOTAL fuel trim is +2.0 or 2.0. The short trim is removing fuel, but the LFT is taking its time to reduce. I've seen this after a repair. The fix was to reset the fuel trims and watch. The engine has about 40K on it and the SFT reads from -7% to +7%, and it stays that way. There's other scenario's, and only by learning how SFT and LFT work with the AFR sensors is it understood. I saw one Ford V10 van that both banks LFT and SFT reading at +25% each for a combined TOTAL Fuel Trim of 50% each bank. This was at idle. As the throttle was opened slowly to 2000 RPM's, LFT's and SFT's settled down with LFT's approximately between 6 to 8% and SFT's approximately between -7 to +7%. At idle, the van shook so bad, I thought the ladders would fall from their roof racks. The cause was a tear in the PCV hose on the bottom of the hose near the port on the throttle body. Ford had an upgrade for this with a thicker hose material. With the the new hose installed, fuel trims came down, no more shaking and all was well in Ford land. The tear wasn't big, only about 1 inch long, but the engine heat and vacuum caused the tear to turn inward toward the inside of the hose. It was that thin! A tech learning about fuel trims needs to work with vehicles that are running good to get a baseline understanding of that system. Disconnect then reconnect a small vacuum hose and watch the readings. I had to learn fuel trims AND the Ford WDS diagnostic system we had before we got the IDS which I understand is still in use. Thankyou for this video.

Great video!!! Was always a little confused about open loop and closed loop but now I fully understand how everything works together. Again, great job and keep up the good work.

Thanks Car Care Nut, I especially like your tip on diagnosing/detecting a faulty Injector depending on whether you execute the Run Rich test or the Run Lean test. Makes lots of sense, thanks again !!

Thanks for your help me learning fix my car problems, god bless you and your family

This is the best educational explanation of an 02, and wide band air fuel sensor I have ever viewed, 😮 and I didn't know about the brake fluid hack on the sensor threads that get stuck. Thank you for sharing.

Great video well explained. Please show a video on live screen when you have a bad wideband or a bad o2 sensor.

Thank you so much for explaining all this. I’m definitely learning. You’re a very good teacher! 🙏🏻

HI, YOUR TECHNICAL INFORMATION ARE THE BEST ON KZfaq FOR THE CASE STUDY THANK YOU.HAVE A HAPPY HOLIDAY

What a fantastic video! Was diagnosing a strange "low fuel pressure sensor signal stuck in range" situation on my Tacoma, but ended up here. Learnt a lot!

You got a sub and a like for this video. Concise to the point and thoroughly explained without overdoing it. Can't wait to watch more and learn more. Thank you

Thank you AMD for another wonderful video. With every video is going better and more interesting (complicated). I found oil change suggestion seriously, after watching video about oil consumption. Today I changed oil after 6 months and 5k kilometers. Guy in toyota dealership was confused why I'm asking for oil change just after 5k. 🙏

Thanks, AMD, your the MAN!!!

excellent as always!!! best automotive educator in yt!!!

Great explanation of fuel trim and how to read the data.

great video, precious information how to look into the data. More of this please...

Very good knowledgeable video. showing the results instead of just talking about them . Today sir you get a raise in pay. Keep em coming.

Dr Ahmed that was a very interesting video seeing how a professional diagnosis technician is able to pin point problems. I start throwing codes with a high mileage vehicle i replace every sensor coils and injectors,looking forward to the catalytic converter diagnosis my rule smell them replace them all along with sensors

Awesome!! Let's go back to say the mid to late 1960's...would you rather be a mechanic back then or at the present? 🙂

AMD I understand now about fuel trim and how the numbers relate. Excellent video and cutting edge knowledge you're teaching me. I will watch a few times to fully understand. I have a Autel 808 scan tool.I need to understand all the numbers. I now know fuel trim. Keep the info coming about scan tools and how to understand all the info they give please! Thanks my friend. Randy

thank you very much.always looking forward to the next video:please keep them coming

This is the video I was waiting for!!! Thanks AMD.

Golden info here, told me everything I needed to know to make a much better pinpoint if I have a fuel or spark issue. Looks like I'll be ordering coil packs!

Thanks for showing how it works. I'm trying to diagnose a p0420 in my daughter' nissan versa ( I know you specialize in Toyotas but i also own a couple two of them. A tundra and Rav4)and wasn't aware that O2 sensors are now wide band sensors. I wanted to diagnose a possible leak in the exhaust system before I condemn the Cat converter. Very informative and much appreciated. 👏

Great Video! Thank you!

This was great. Dont know why this video didnt show up in my feed before.

Thank you! That was very interesting. Please do more of these diagnostics with other probable troubleshooting scenarios using live data. . Maybe you could use the xtool D-8 scanner. That's the one I recently purchased. I'm a life long auto student and I consider you one of the best Toyota Guru's out there. God Bless

Thanks for showing what normal live data looks like!

Your explanations are top notch! Really enjoy watching your videos!

Great video! I learned a lot from this! Thank you for taking the time.

AMD thank you so much for making this video! I have been trying to teach people this exact concept for years! Well explained!!!!

Hey ! hello from Geneva Switzerland, I discover your channel and it's always very informative and detailed, thank you for all this work !

Thank you so much for all the info on FT, Very very good video !!! Keep up. 👍

Thank you for this and all your videos. They are all very much appreciated.

I feel like I signed up for a Car Tech Class and they forgot to send me a Tuition Bill! Glad there isn't a test at the end.

Really great video. The best I've seen on the subject. Thank you for making it.

Thank you so much for all your videos ! You've been helping me so much lately!

Great video, Thanks, Love it!

Excellent video but I'm going to watch it again and again so i can really understand fuel trim.

Thank you sir for the excellent Toyota classes. 😊

You're Great!! thanks so much. If only Dealers and the Govt. would invest in people who have a propensity for understanding this sort of thing instead of wasting so much money trying to send people to college to "learn" about ridiculous degrees. I considered changing into automotive repair 20 some years ago. With my strong electrical and electronic back ground I really loved this stuff as a shade tree mechanic learning about the emissions and such on my cars. But I did not do it. I really think auto mechanics need some specialization , if it doesn't have it already. The cost of cars and their repairs is too much for our people and economy. We need better groups of technicians working together to solve problems faster. The cars themselves are amazing. Of course we need, maybe a better mix of technology and lessening the demand for continually better emissions and gas mileage.

Excellent video and explanation.. Many thanks...

This clears up a lot for me!

very useful AMD. I am awaiting my first scan tool to sort out problems on my "new" 98 4R.

Thank you so much l. I learned a lot. God bless you

Thank you, sharing your knowledge is really appreciated, helps a lot.

Thanks for your orientation, could you talk about oil based in natural gas , like Penzoil here in 🇺🇸, vs convencional oil made from petroleum?

Educational video... sure could use a scope of some sort. ...... Question.... fixing to buy a new auto....Looking at the Lexus RX350L and the Mazda CX-9. Any pros and cons of each? Appreciate your input' The Mazda is cheaper but that is not the issue. It drives nice and has low torque. The Lexus is comfortable, etc. Appears similar to a Highlander.

Professional seminar. Thanks!

Great video with pro tips! Thanks for sharing!

Outstanding presentation.

Amazing video! I'm diagnosing my Lexus RX400h since it's throwing a "too lean" error constantly and my AFS voltages are off the charts (hitting down to under 2V and up to 5V) and also my Fuel trims are also going crazy (Long FT would even reach 50%) and then my Injector port goes way too high at 5ms so something is certainly going very downhill with the engine. Looking at possible air leak (hopefully that's it) and will also be looking into changing injectors as a start.

Thanks a lot! Using a cheap blue drive I could diagnose my CRV bad MPG. It was a O2-S1 sensor which is dead at 1mV!!

Really good training video. Thank you for doing these.

i know this video is 2 years old.. Great explanation.

I just replaced the downstream o2 sensor on my 2011 rav4 4cyl 130k miles and prior to replacing the sensor i have mentioned the readings below but after replacing it at idle the long term fuel sensor is at 0% and while cruising at 75 it’s at 7% but it goes up and down based on throttle position. So I think there has been a significant change after the downstream sensor replacement. I will keep an eye on it and read fuel trim numbers

Really liked the explanation on both short and long term fuel trim. Always wonder how to read that type of data. Thank you so much for that information.

Absolutely love this episode. I am poking into the fuel trim on my 98 and 99 Camry. My Camry is in fuel trim rich condition under idle (about -7%), but they would go back to normal under driving condition. I suspect it may be due to a partially clogged IAC. I wonder if there is standard / reference values under idle for use to compare to.

Great explanation of fuel trim…

Very informative. Great video 👍. Many thanks.

great explaining

That was great and, on the contrary, not long enough! But I'm not complaining 😊

This is absolutely amazing. Thank you

Thank you for the EXCELLENT video. It was very informative. You mentioned "don't chase a 5% fuel trim." I understand the logic behind that. But at what % should one become concerned? I heard somewhere plus or minus 10% long term fuel trim is acceptable. If more than plus or minus 10% long term fuel trim, then the underlying cause of the fuel trim adjustment should be examained. Did you agree?

I learned alot with this video thanks for your effort

This has me thinking my injectors are very dirty. That my conclusion after watching the last 15 minutes. If i cannot find a vacum leak, and i have sprayed ether everywhere i could!

The demo was not too complicated. the complication that could use some of your strategies is how to do this on the hybrids (e.g 3.3L V6). the issue is that the engine will shut off when we need idle data. driving at a steady slow speed is also not too practical since the hybrid will turn off the engine and run on batteries. dragging the brake-maybe? ideas? thank you

I am from Algeria you are the best

Awesome! thank you granted my request.

Great input thanks

TOYOTA SHOULD USE THIS FOR A MODULE WELL EXPLAINED

Thank you for your videos. Any recommendations of how much grease to put in 2016 4 Runner driveshaft slip joint? I have read 4-5 pumps, or until the slip joint moves, or until grease starts to come out of the slip joint seal. The u joints are straight forward, but the slip joints there is a lot of confusion. Any advice would be greatly appreciated. Thank you 🙏

Hi, thank you for the info. what is the difference between the fuel trim and the O2 fuel trim bellow is live data from GDI Engine Toyota TOYOTA Avensis I 2.0i-16V model (AZT220L) VVT-i Engine 1AZ-FSE Year 2001 petrol. What is the difference between short/Long fuel trim and the O2 FT? Short ft 1 -20.34 % Long FT 1 -0.04 % Short ft 2 -14.09 % Long FT 2 -0.04 % --------------------------------------------------- O2FT (bank 1 sensor 1) -20.34 % O2FT (bank 2 sensor 1) -3.94 %

Thank you for the amazing videos!

could u do more on reading live data/ or just data in general, i have a Foxwell nt650 elite scan tool that i purchased on ebay of about $170, it has many functions and data but i dont kno wut it all means, thank you

Great demonstration! Best explanation on fuel trim diagnosis.