How Variable Valve Timing Works

Here's how variable valve timing works on your car's engine. In this video a variable timing gear, actuator and engine head is taken apart to demonstrate how the system works.
The variable valve timing, or VVT, allows for a phase shift in the timing of the valve opening and closing. It does this by offsetting the camshaft at a relative angle to the timing chain.
The VVT gear is a fixed gear when there is no timing advance or retard. However when the computer sees it necessary to change the timing, the gear fills with engine oil.
Passages inside the engine head allow oil to flow from the pump to the variable valve timing solenoid. The ECU controls this solenoid to allow oil to enter the VVT gear. The gear will unlock its fixed pin and then become two independently rotating pieces. The pockets inside the gear fill up with oil causing an angular offset between the input (chain) and output (camshaft).
The system is controlled by the ECU using the cam position sensor for closed loop control. The angle of the offset is infinitely variable between zero and 15 degrees or so.
Please note, VVT is different from VTEC or VVT-L. Those systems use a separate cam profile that varies the lift amount, duration and phase. However since the cam profile is fixed, it is not infinitely variable like VVT is.
Varying the timing of the valve's opening and closing will result in cleaner combustion, generating either more power, or less harmful emissions.
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Follow me @speedkar9 on instagram for behind the scenes!

[@trippm4036]

I don't know what's more genius... the design of variable valve timing or your videos explaining how It works !

[@speedkar99]

+Tripp M I'm the genius here.

[@ทําง่ายให้ยากชาแนล]

@@speedkar99 yes. Sir. U r the best.I really like to watch your video so much and also I am watching the other video from u.This is a good chanal to me. Thank you again.

[@garittlajoie8841]

Well said

[@hugostiglitz1109]

You ran out of your brother's underwear?

[@pmxquality]

Agreed! This video is the perfect explanation as to how the system works.

[@garyvallone5393]

One of the best videos I've seen. 100% clear and thorough information. This guy speaks like a true Genius! Great job!

[@speedkar99]

Thanks for the feedback

[@joesteffler8216]

Hands down one of the best "How it works" videos I've seen.

[@modeljetjuggernaut4864]

This was 6 years ago..How did i miss these videos?? Shit man...

[@speedkar99]

I got lots of videos like this, check them out!

[@harrystamper2665]

Brilliant explanation of all aspects, especially the feedback loop via the camshaft position sensor. Like your enthusiasm too!

[@noahmaurano181]

Perfect explanation of the VVT. Seems like every car after 09 has a Variable timing system.. Thank you!!!!

[@speedkar99]

Yep, it's the way of the future

[@_funkytorino_]

More than 4 years have passed... Very well explained, so clear. Thank you very much!

[@jamesvonfunck]

Best explanation on this topic on the internet. Couldn't ask for more.

[@speedkar99]

Thanks for the feedback!

[@outdriving08]

Great video, have been struggling to understand how the oil flowed to the gear but you've explained it perfectly. Cheers!

[@speedkar99]

Thank you

[@dransari100]

This is the best explanation I have ever come across for variable valve timing.

[@speedkar99]

Awesome

[@garmin1488]

Best explanation I've seen so far thanks for posting. Can't emphasize enough the need for oil changes and monitoring your oil level.

[@speedkar99]

Agreed

[@anaeleraphael8725]

You have demystified the vvt technology. Thank you very much. Nigeria.

[@speedkar99]

+Anaele Raphael your welcome. It's pretty simple

[@danl4222]

I agree with those who say this is a great video. Well articulated. Also he talks fast ..but not too fast. I learned. Thank you

[@speedkar99]

You are welcome

[@rajlovinglife]

Shows how much effort you put in making these videos such a great way of explaining things ..wow ..nice work man..

[@speedkar99]

Thanks, I appreciate your kindness, yes there is alot of research and effort that goes into making quality content

[@stalincampbell8574]

That was well explained you're the first person to explain it with so much clarity

[@speedkar99]

Thanks, Clear and to the point is my objective

[@anaeleraphael8725]

Your teaching fast and engaging and touching every detail. There is a huge difference between this video and that of others who thought the same topic.That multimeter idea is very scientific.

[@speedkar99]

+Anaele Raphael I'm glad you like my teaching style, che k out my other videos for more.

[@ally4kava]

I love how u dnt waste time.. U get straight to the point and cover everything

[@neillellman1915]

You explained this so well! Thank you so much, I understand the function of the VVT and the auxiliary components a lot better now. I wish you could branch out into tattoo machines too, because the way you explain things is awesome and thorough.

[@joeydf28]

You are a great teacher. This video is awesome, like virtual textbook being taught in a Classroom. Well worth it and I will watch this many times.

[@speedkar99]

Thanks

[@SIDEKICKONYOUTUBE]

VERY VERY detailed and easy to understand explanation. im NOT an Engineer nor a Mechanic but im beginning to understand how it works.

[@Th3Mafia]

the amount of info in this video....... is priceless, i have to say, this is such a comprehensive coverage of the subject...... maybe some people wont get it all on the first shot, but as you go on, i can see them rewatching it and getting it. great vid man!

[@DadsGotADeal]

amazing explanation! i read and read about vvti and it was only this video that made it clear for me! thank you!

[@mikeedwards6610]

Outstanding sir!! Talk about bang for your buck!! That was likely in the top 10 of the best 8 1/2 min I've spent in my life!! Thank you

[@juancabrera-ru9jx]

This is the best and most in-depth vedio I've ever seen on how variable timing works. I love your vedios, keep up the great work!

[@speedkar99]

Thank you

[@AF-jx4lt]

Great video! Thank you for doing it! I'm working on my car now and this helps me determine what's needed.

[@arztv1962]

Now I know how useful the toothbrush is in learning this :)

[@thehumbleonez4030]

Speedkar you just gave me a college education on automobiles..thanks

[@speedkar99]

That's good to know!

[@shingabiss]

Very elegant and precise presentation! A closed loop system with the cam position sensor as feedback mechanism to computer for vvt oil pressure control.

[@AndriiOstapchuk]

Thank You! Came from Vanos BMW to V-tech Honda K24. Failed to set timing on K. Couldnt get idea how that Intake sproket works. Gonna give it another shot. Every time intake cam goes off alignment.

[@speedkar99]

Does the VTC pin lock when you rotate the engine?

[@Yathuprem]

Waited so long for this. Nice video. New toothbrush??

[@speedkar99]

+Yathu prem thanks, I knew you were waiting :) Yes fresh toothbrush from my brother

[@Yathuprem]

speedkar99 VTEC is a lot different??

[@speedkar99]

+Yathu prem yes Very different, the cam shafts actually have different cam lobes on them and it changes profile. See Engineering Explained's video on VTEC vs VVT

[@syedusamamanzoor1838]

you have a very generous brother... haven't you? :P

[@maclanphere5674]

mid-video, like a wardrobe change

[@baterizmo]

...and that was a couple of gran worth online course compressed into an 8 minutes free video.... brilliant

[@speedkar99]

I'm glad you appreciate my work

[@herbertsjeffrey]

100% UNDERSTOOD . . . NO AMBIGUITY. YOUR ABILITY TO EXPLAIN CONCEPTS IN ENGINE DESIGN AND WORKING PRINCIPLES IS ADMIRABLE. . . IN SHORT, I THINK THIS CHANNEL IS A TREASURE.

[@mechanicable5741]

BEAUTIFUL!! I just sent this to someone to emphasize the importance of oil changes. besides wearing out the internals and bearings and cam journals, you'll also kill the valve timing mechanisms. those small holes will clog.

[@Davethreshold]

AAA+++!!! I have seen a few of these, and could no get my head around it, (pardon the expression) and now I understand it perfectly!

[@andresguraieb1947]

Best explanation I've seen so far on VVT. Thank you!!

[@speedkar99]

You are welcome

[@LitchKB]

Dude every time I'm clicking through videos on YT, seeing that toothbrush just kills me XD. You got me. Subbed.

[@AlexxanderOnYoutube]

you have a really good vocabulary

[@speedkar99]

Hmm no one has told me that before. Thanks

[@andrewchristiansen8311]

I mean, he did say nitrous oxide when he meant carbon monoxide. But he is way better than Biden hahahaha

[@douglasholt9337]

Great! Concise explanation. No jungle beat music. Thanks.

[@speedkar99]

Thanks, I try to keep things short and to the point

[@roboedar]

Dude... Such a great, thorough, easy to understand explanation.

[@speedkar99]

Thanks

[@RobertMkony-u7j]

Very well explained even the newbies understand clearily!

[@Salmon.dunlap]

thanks a bunch, valve timing has been kicking my ass in school

[@typerightseesight]

literally first video on this that made sense ty.

[@natarajanganesan9321]

Good one. Simple to understand. Perfectly explained. Thanks a lot.

[@speedkar99]

+Natarajan Ganesan your welcome!!

[@seshachary5580]

AWESOME EXPLANATION THANK YOU

[@Spartan195X]

Finally a video explaining well how vvt works. thank you great video and pretty well explained :)

[@speedkar99]

Thanks

[@greetswithfire1868]

This whole system is dependent on oil flowing though these small passages. Change your oil regularly.

[@narlycharley]

And use a high quality oil and filter. Fram Ultra filters and Pennzoil Ultra for me. $25 for five quart jug on Walmart's website and filters on eBay that come to about $5 each. Change your oil every 5-7K miles and you're good to go!

[@speedkar99]

Agreed, oil is very important even more so for newer engines with tighter tolerances and thinner oils

[@mikejones-vw6hq]

Good advice, I would also recommend checking your oil between changes. Late model engines especially the 4 cylinder GM's consume a ridiculous amount of oil (1qt/3000 miles) at that rate if you push oil changes farther out you can easily be 2 or more qts low. See cars at our shop every day running like crap with no oil on the stick.

[@COMMANDER-ONE]

Excellent video! I Understand everything you described!

[@maxforever26]

mike jones Very much agree. Having that issue now with my 2013 Highlander.

[@partsshooter]

I just need to add one thing that's incorrect...Great video btw. At 6:13 in regards to the oil pressure, the oil control valve inside the oil pump is what regulates the oil pressure, at the bottom of that oil pump is housed a plunger and a spring, where that bolt is. that spring relieve itself at a specified pressure, that basically keeps the pressure in check for the entire engine

[@lelandlewis7207]

Just a point of clarification: advancing a camshaft increases low-end power, retarding a camshaft increases top-end power. As little as 4 degrees can make a big difference in the effective rpm range.

[@speedkar99]

Good to know. Thanks

[@ValentinArzola]

Awesome video by the way. Hadn't seen anyone explain how the phaser relates to the VVT and overall engine timing mechanism.

[@MrSupernova111]

Amazing! I've very impressed with both your presentation and Honda's ingenuity! Thanks!!

[@speedkar99]

Thanks but this wasn't Honda

[@blainemiller8533]

I'm guessing toyota, 1.8

[@luccicorp]

It's 2022, but you just gained a new subscriber. Great videos 👍

[@speedkar99]

Thanks for subscribing

[@7999rahul]

best explanation i have found so far. thanks!

[@speedkar99]

You are welcome

[@AlanPertab]

Great explanation of the variable valve timing!

[@speedkar99]

Glad it was helpful!

[@viciousocean]

awesome video!! this guy should be a car engine designer or something like that !!!

[@speedkar99]

+dayalan pillay I actually just applied to Toyota Canada yesterday. Let's see what happens

[@chuckfischer7202]

Thank you for brushing that subject.

[@speedkar99]

"brushing" 😏

[@brentonlee7071]

Wow this video is brilliant. I learned so much in 8 1/2 minutes.

[@condor5635]

One again Speedkar99 you nailed it. Learned something new again. Was waiting for your brothers’s underwear to make an appearance! Thanks for another great one

[@HectorAlvaradoJR]

A true engineering marvel.

[@sicaria0azteca]

Thanks a lot, video totally explained all my questions!

[@speedkar99]

Glad it helped

[@friedelpeters6722]

Best explanation presented with great authority. 😊

[@michaelmardini346]

finally some clear explanation. Thanks!

[@speedkar99]

Your welcome

[@Smart-Skippy]

Props Speedkar99. You make easy to understand, easy to watch videos. Respect ! 1. Your toothbrush... Can I borrow it ? ;-) 2. Your gloves grew fingertips! Woah !

[@andrewchristiansen8311]

Thanks for making this I have a 2.4l Toyota AZ motor so I wanted to know how it worked. I get the concept just not the execution. Thats crazy they use a solenoid to used a oil filled "clutch" to adjust the timing to multiple positions.

[@jamesosekowsky8303]

Wow! Wish I could be that great in explaining.....anything. Great job!

[@aros007z]

Boy how did you learn all this stuff? You are incredible!

[@speedkar99]

I research it online then titivate with the engine to make sense of it all

[@luchofly]

Man.... This guy really knows how to make informative Videos. I'm hooked to this channel. Keep it up.. !!! Ohh.. And the toothbrush as a pointer is really Original, lol

[@speedkar99]

Thanks! I'm glad you love my videos, please share and make suggestions for new ones.

[@carlosnava3126]

Speedkar99 u are awesome. Great videos

[@speedkar99]

Amazing

[@cleansebob1]

Best explanation I've seen. Great job!

[@speedkar99]

You are welcome

[@Pod-042]

Thanks for the class.

[@thedrivewayC3]

Excellent video. Just the info I was looking for to start in on a timing issue.

[@BadRobot5]

awesome. that was a perfect explanation. you solved my problem in my vehicle. thanks....

[@speedkar99]

Glad it helped

[@iamalive9807]

Awesome guy..nvr failed to explain anything..ur must hve a doctorate degree..well done bro

[@speedkar99]

Glad you learned something

[@thebateman7949]

If he does have a doctorate, it's a DDS. :)

[@davidmarberry5565]

great explanation, i think my old rotax engine in my ski-doo snowmobile had a variant of that theory and i know it worked quite well greatly increasing power especially low end torque , thanks

[@speedkar99]

You are welcome

[@donaldhollums3278]

An informative film, I'm subscribed. Keep up the great work!

[@jithinvijayan3]

Still trying to understand..difficult topic for me, thank you but you explained very well.

[@speedkar99]

+Jithin P V I hope my explanation was sufficient

[@jithinvijayan3]

speedkar99 Sure, i haven't gone through this much to the core topic that's why.

[@speedkar99]

+Jithin P V ah i see, I aim at those who have a little bit of automotive knowledge, if you want some background, take a look at my how an engine works video.

[@maikelnait4495]

Your videos are addictive!!! Can’t thank You enough ❤️

[@lesterpenner8786]

Toyota just replaced the timing gear on my 09 Rav4 2.5L it had a cold start rattling. It costs just over $1000.00. Now it starts normal and also has more power

[@rangerrick8220]

PS - I bought the car used with only 37,000 km on it and it appeared to be immaculate in condition. Since then I have been changing the oil and oil filter every 5000 km with Mobil 1 Extended Service 0W20 oil and OEM Toyota filters... yet the problem remains.

[@fieldsofomagh]

Great info on vvti and realistic explanations !!

[@speedkar99]

+Tom OConnor thanks for your feedback!

[@Akuma-jx8dr]

very well explained, only had to watch it once. Nice job

[@robincondite]

Wow. So fast and informative! Thanks!

[@ChunkyMonkaayyy]

Pretty cool stuff. Thanks for the explanation on this and every other video!!

[@speedkar99]

+Hugh Jafro Awesome

[@walrus4248]

Thanks! Great visual aids.

[@speedkar99]

It sure helps to see actual parts

[@jafaary2614]

best explainaition video so far . thanks man

[@simeonrush]

Thank-you so much for this video my cars bogging out uphill and under load and throwing p0016 p0017 codes the timing chain is correct so will take apart my vvt gears thanks for this info :)

[@speedkar99]

Hope it works out

[@Aaron5644189]

Excellent instruction on a very complex system.

[@davminks]

It seems this is a common symptom on older Japanese vehicles, where the control valve is broken, sticky, delayed, or any nearby mesh filter is clogged. What will often happen, at low rpm, the car will feel sluggish and may hesitate to engage timing adjustment, this can sometimes be felt as a delayed engagement to higher rpm state, occasionally followed by a noticeable ‘thump’ as the cams timing adjusts late. You will also probably feel it when decelerating. You may also notice a light puff of smoke (unburnt fuel) out the exhaust when the timing adjusts. The delay/hesitation will reduce fuel efficiency and power delivery as acceleration won’t get the timing adjustment at the exact moment it is expected. The car will feel out of tune and may rumble at low rpm under acceleration. It can also be noticed at higher speed, and is sometimes misdiagnosed by DIYers as a transmission (torque converter) issue. If the valve gets stuck and does not engage at all, you will most often get a camshaft position code for the corresponding valve of concern. If a camshaft code appears just once, the control valve likely failed to deliver oil for adjustment only THAT time. If the code re-appears continuously, you already have a gear issue or timing has jumped. Best to get it resolved as quickly as possible, before you end up with that infamous vvti gear rattle.

[@manos84305]

Excellent explained . Many Thanks

[@ibadurrahmankahfi]

Your explanation is excellent... thank you

[@speedkar99]

Welcome

[@sonicdewd]

Please note - BOTH the pump and the valve develop the oil pressure. (You are right in that only the pump provides the oil flow.) This is a common discussion item on a lot of threads. Pressure is developed when the entire vessel that the oil is in provides pressure on all sides of the oil sample. All sides. That means in this case, you have oil pump, oil valve, oil galleys, everything oil.

[@ryanv7195]

Wow wonderful explanation! I'm going to subscribe even tho this is the only video of yours I've seen. Great job!

[@jeromealexander6906]

This was a very detailed video

[@speedkar99]

Thanks

[@hussuanmko4366]

Thanx for your explanation about cars.

[@speedkar99]

+hussuan mko glad you enjoy my series!

[@katariajaymin205]

Fabulous explanation

[@sukritbhattacharya9992]

Amazing knowledge

[@71druss]

As always another Great explanation and very well spoken,

[@speedkar99]

Thanks

[@sajsed2]

Thank you for the amazing info

[@speedkar99]

Your welcome

[@guitarlespaul8]

You would be an amazing teacher! Amazing video, great explanation!

[@rajcha5625]

You make it so simple. Cheers :)

[@speedkar99]

This part is simple. When you get to how the VVT affects the engine efficiency that's something to wrap your mind around.

[@stephenspears6640]

Great explanation. Appreciate the video!

[@speedkar99]

Glad it was helpful!