Inside a Toyota VVT-i Camshaft Gear! 

I have 2007 Corolla with a 1zz-fe 1.8 4 cylinder, I was changing the timing chain and the VVT moved back and forth. I removed it from the cam and it rattled inside. Took it apart and one of the leaves(?) of the rotor had broken completely OFF! That was the rattling sound the engine made when started. Changed the VVT gear and no more noise!

The pin has two functions. To locate the cam during start up and as a safety feature if there's an internal oil seal leak. When this occurs the pin will lock in and the ECU will recognize that the cams aren't adjusting at various engine rpm and load points. On each VVT unit there will be 4 sensor points that are spaced uniquely to allow the ecu to know what degrees the cams are set at.

I remember taking apart a 2jz vvt-i cam sprocket and was a very different design. Just shows how Toyota has come up with a new way to do the same job more efficiently. Granted it is not as aggressive as a V-tec system which has a different cam shaft profile when commanded but this is how Toyota gives you the performance timing when it is commanded by the ecu when a certain rev is matched.

The pin locks everything in place. When VVT system needs to change timing, oil is diverted to the pin, pushing it open against the spring, and allowing the gears to move. When oil pressure decreases, the gear locks back into place.

Those orange blocks are seals just as you would have rings in pistons, to seal pressure from leaking, except these are vertical seals and the spring ensures that the seals maintain a tight seal against moving parts.

VVT-i is turned on at set points that use throttle angle and engine rpm as input signals. The engine ecu has a map and when the inputs are good it turns on an "oil control valve" that sends oil pressure to the vvt-i gear to turn it on

My 2007 IS350 was making the same sound from a cold start. Finally after months I just took it in and it was vvti gears worn. My warranty had expired but the dealership still did everything for free since I had brought the problem up to them in the past and they had it recorded in their system. This time they were able to figure out what it was. They replaced all sorts gaskets, cylinder heads, camshafts, and more. Probably would have costed me tons of money but thankfully I got taken care of.

The vct solinoid has one input oil feed and two output, the two output one for retarding timing and one for advancing. As rpms rise the phaser will advance. It keeps the engine in optimal timming. Hence spark firing early btdc

The pin is a hydraulic piston that stops the cam from changing timing when theres no oil pressure. Its so that the cars timing is locked at startup and any time that the cam isn't under computer control. BTW The computer uses the lugs on the camshaft to continuously time the cam using a solenoid on the block.

If you start the car there's no oil pressure and that pin prevents the VVT from getting hammered to death. Oil pressure builds up and hold the pin in against the spring until you shut the car off.

If you're working on this stuff then yeah having a set of bits is definitely a good thing. I find vice grips do the trick nicely haha. Thanks for the feedback!

The "Orange Blocks" are oil seals. The mechanism works via engine oil pressure, in a push-push arrangement. The ECU determines the position by varying pulse widths to the variable timing control solenoid. A square wave (equal + and - time intervals) holds current timing. Narrowing or widening the pulse varies the timing. The pin is to lock the timing until oil pressure has been established. Exhaust timing is fixed.

So, is it super bad that i was able to unlock mine simply by turning it? im in the midle of amajor teardown and inspection of my timing system because of a drivability issue, and i remember just one time that mine made the cold start grinding noise many months ago. Perhaps my lock pin is rounded and therefor not locking when its suppposed to. My analysis of it with my eyes and brain suggests that the lock pin is there to stop it rotating until there is oil pressure, so as to stop the cold start rattle and also to stop it form moving out of time while there is no oil pressure to hold it in time. I was undoing the little torx bolts to inspect it, (without the chain) and it just slipped, then i realised i could lock it again by turning it back, thne give it a hit with my palm and i could unlock it. Now im wondering if this is happening randomly causing my stuttering at idle, and maybe even the reason for my lack of power and code p0341, which i thought was a stretched chain.

The pin is spring loaded to hold the gear in place once you reach a certain rpm or speed the oil pressure will push the pin up allowing the gear to rotate vtec vvl-i cvt ect are all designed to give a boost in power on the hi end for passing or fun the pin keeps thing from moving till needed to preserve fuel economy

The pin keeps the cam and gear locked together when their is no oil pressure like when starting the engine.

I get a 1-2 sec loud rattle when I start up my 2016 Toyota Camry 2.5 L engine... could this pin be the problem? Someone told me this cam gear is draining back oil when it shouldn't...

The VVTL-i is even crazier. I love the 2zz-ge, One of the most personified engines I've ever experienced.

The tap,ered pin is a check valve that is kept in its hole by the spring on top of it.as the RPM goes up , so the oil pressure, which will unseat the pin , hence the rotor will move to advance the timing based on the conditions. When the engine rpm decreases , so the oil pressure, and the pin goes back to its seat. Thanks

Let's say VVT is for intake only and exhaust has a conventional sprocket. VVT sprocket has a range of movement, like you show - up to 4 teeth, exhaust sprocket is fixed. Where does the chain slack to allow for this movement come from, are VVT engine chains inherently loose to allow for this movement? EDIT: I might have figured it out watching T0G5KLN4a_w. The sprocket doesn't move in relation to other sprockets, what moves is the camshaft itself in relation to VVT sprocket, thus no chain slack is needed, duh.

The gear advancing the timing is advancing pretty cool tech

The same problem have my car, making noise when I start it...😫..I have to change it..where are you located?..

that advances a lot more than i thought it would

The mechanism looks very simple and pretty much self explanatory. The pin and the opening for it look good. I wonder why the pin fails to lock? Perhaps the spring breaks or something gets stuck in the pin cavity thus restricting or preventing it's movement. My wifes 04 Camry (2.4L) has been making this noise for over 100,000 miles. It has 190k on the odometer now. So far it has not caused any issues.

That has 5 star tamper security screws because it is a critical part of the engine that can mess up the car really good if you put it back wrong without the proper way to do it. There is a reason for that part being protected. i have mine from an engine which head I am rectifying and this engine was run without oil to the point it failed with oil all burnt inside it. I wonder if inside the VVT-i gears there is still oil burnt that would impede its functioning right; it was washed at the machine shop off the oil externally but wondering if inside needs to be cleaned as well; but i am told by many mechanics to leave it alone and not to take it apart as it may mess up the car later on.

it adjusts under pressure when it reaches around 5-6000 rpm the pin releases the cam that gives engine a boost up to 9000 RPM its called VTEC

the spring loaded pin is to hold the cam at that timing for starting and only disengages after it receives oil pressure

the vvt gear also when pin pops out keep exhuast valve open longer at higher rpm to prevent head gasket from blowing why these motors are bullet proof only way to destroy a toyota is to throw a rod through the piston no oil no collant

VVT-I does not have lift like VTEC ,only VVTL-I does..The pin locks the gear in place ,until the VVT-I solenoid allows oil to flow into the gear and then the pin moves and allows the gear to be free to move and change timing and the intake and exhaust valves over lap each other at times to optimize fuel efficiency and lower emissions.. FyI: VTEC uses different cam lobes with larger and longer duration to create lift,VVTL-I uses a pin that is moved by oil to increase duration and create more lift..

Cool, I wonder what kind of metal they use for the seals. Thanks for the comment.

Thanks Steven. I'm glad you enjoyed the video so much.

wait... couldnt you have purchased the 5 star heads to disassemble normally?.. where you crunched on time?

thats the reason for the spring loaded pin it is to control how much adjustment you can get en there is a oil pressure from below that pushes that pin up as you know oil pressure raises with the rews

Have you tried using Full Synthetic Engine Oil? My Corolla, used to making a rattling noise, till I changed oil, I use Penrite 5-40W FULL SYN.

I bet that is the rattle you hear in the gear on cold start up, that spring has lost tension and is not locking the gear like its suppose to and the gear rattles back and forth on that pin with the weak spring. Honda has the same design, on Honda I stretch that spring if it has cold start rattle and reinstall it then the the cold start rattle goes away, I bet its the same on this cam gear.

Hi, thanks for your video. One question, I have a 2008 Toyota Corolla with 230,000 km with a manual gearbox. The fault is that when turning on it starts with 1300 rpm and as it heats up they go up to 2000, that is, it is the other way around since I understand it should drop to around 900 rpm. and already hot I go out and when I make the gear changes I see that the rpm oscillate between 2000 and 1000 rpm and when I continue the march the minimum is 2000 rpm. If I leave it running stopped the car stays at 2000 rpm. I clarify that with a scanner it does not give an error. Well we removed the carburetor, total cleaning including the MAF sensor of the filter, to clarify, you cannot remove the IAC valve to clean but the carburetion body was submerged in non-abrasive removing liquids and a lot of dirt came out. We measured TPS and IAC with a multimeter, we simulated with power and everything was fine. We checked the pipes that had never been touched and they were impeccable. We put everything together and it starts making the same failure. We took out the VVT valve, it was cleaned with carburetor fluid and wd40, I have original oil in the car, of 5 original toyota viscosity, I excited the solenoid with 12 volts to the vvt-i and it works well, I don't improve at all either. So I disconnected the EGR vacuum valve and there the rpm's dropped a little but after five seconds it accelerates and when connected it returns to 2000 rpm. If I disconnect the MAF sensor, the fault disappears but the engine idles low between 300 and 500 rpm's and the car loses power at 3000 rpm's and the brake is very hard. You can help me?

Its a adjustable cam gear, like some after markets are sold from HKS etc. This concept is old. Check the 5SFE and the 3SFE engines, but these engines, the gear is exposed and the gear is divided in two and it only moving one part of the gear, while the other one depends (exhaust) depends on the other one for advancing or retarding the timing. These, VVT-i, are more efficient with more timing advancing or retarding timing.

The pin is to lock the cam in the place to start the engine when there's no oil pressure.

There's oil pressure on other side of the pin that pushes against the spring that depends on oil pressure due to the speed of the engine

I have a 2001 lexus is300 my mechanic change the timing belt and seals, he pull it out the vvti gear, now wen we start the engine, engine start with a click noise, he said it's the vvti, so the vvti can be adjusted? And can get that clic noise?

Vvt gear needs to unlocked before taking off cam,( try dissembling the vvt like he did ONLY IF REPLACING WITH NEW ONE then take off cam bolt)if you don't it will grip the guide pin on the back of the gear making it very difficult to take off, do your search very carefully it took me hours of research online on how to approach this. When you install back the vvt gear needs to be unlocked( look at the dots on the housing) and make sure it seats nicely in the right grove, torque to specs and the turn clockwise on the vvt gear housing then you hear a click and to make sure you locked the vvt look at the dots they have to line up together if is not its still unlock. ( Toyotas of this design are prone for 1 second start up rattle and that lock pin is the culprit)

I have a question my car (lexus is 350 ( 2gr-fse engine VVTI) Every morning When startup Engine sound (rattle-noise) A little bit of time Only when the engine is cool Some say (ADJUSTER ASSY, VALVE LASH) Others say VVTI ( CAMSHAFT GEAR ) Is the problem of VVTI ?

You are missing a plastic end at the bottom of the spring. If you watch closer, you don't see spring marks on the back of the metal plate (i opened up and fixed a nissan vvt; i might create a video later with it - what was faulty and how to fix it)

Allow me to comment your video: - If both camshafts has a cam gear, than we call it a 'dual VVT-i'. It means it adjust the valve timing of the intake and exhaust valves. 'VVT-i' only adjust valve timing of the intake. - actually it's the innerside of the cam gear that moves. That innerside (star shape) is fixed to the camshaft. Just saying so nobody misses. It's just because it's clamped between the bench.

Guess that plunger spring is what gets weak and causes the first start rattle noise. And if you stretch the spring to create more tension the rattle stops.🤔 Interesting.

Can this sprocket make noise in the engine when the engine is rotating 🤔🤔❓

wonder what type of metal the vvt gear is if it can shatter

Very informative, and in pretty good Canadian English, with "zed" for "Z" and everything.:) Thanks for posting!

As the engine turn the timing changes as rpm go so does the timing changes intake and exhoust

Impressive ,genius for this vvti maker👍👍😁

thanks....i have one and trying to determent if has a filter in the system....thanks again...bob

Not an expert but I am guessing: the removable "pin" you are referring to that locks the gears does exactly that - It locks that adjustable rotation in place when the car doesn't want to use it. The spring seems to help the motion of unlocking and locking. Looking for an experts answer.

Hi the second gear you showed has a pin that holds the spring. how is the pin fitted and what type of pin is it? does the pin adjust or fixed. thinking of glueing one similar type of pin.

Thanks for the video and many of the good comments made by others. Was wondering what was going on in there. :)

Those bolts have E socket bits handy to have if you work on Toyota a lot

I have rebuilt the VVT and now it takes about 80 psi to unlock it....?.....thinking it might be a little too tight now?

The intake cam you have shown doesn't seem to have the secondary lobes for the valve lift. So I'm pretty certain that it's a VVT-i cam not a VVTL-i cam.

what type of rattle sound does it make ??? have you noticed it make any effect on the car ???

I’m looking into locking out my phaser gear in my Nissan and using sn msd box to control timing at top end rather than this mechanical one that can’t hold on to a turbo.

i have a 2003 es 300 that is making a noise when started and is getting worse. I posted it but have not figured out what the problem is.

Thanks for the video. My 08 tundra is making this noise with 130,00 miles on it. My question is should i take it in for repair or will it be alrght in this condition?

Really good explanation. Thanks for the video

some newer toyota dual cam v6 engine are interferance. ive seen a t belt water pump changed and the cam rotated to much at tdc with the belt off and when he was done it had a consistant ticking noise(slightly bent valve). 3mz v6

Would a failure on the vvt-i cause the timing to be too advanced and a random misfire P0300 code?

High oil pressure makes things happen. Best part of more moving part is they break. Good on paper but when it fails. Do you have plastic?

just for history due there is no tool for loose bolts as you already know :) you "bite" the head of the bolt with the vice and you turn the cam.the bolts r loose easily without drilling.the pin is securing the cam to a certain position under 4000 rpms or when there is no oilpressure (for morning start up or for 2much worn out spoket.there is no use for trying to fix the vvti part,some the plate is worn from the spring and you cannot out it in another hole,the bolts r off centered!great video man

Yep that’s IPR I have the set and have never used it bought it by mistake thought it was torx

Hello sir I have a problem with my toyota altis 1.6 manual rattling noice at start fir 1 second then disappeard Can you help me regarding aolution of this problem

5 point bits are TORX-PLUS and are readily avail

In our 2009 Corolla, this thing makes a loud rattling noise just for a second at startup. Very annoying sound. Toyota dealership claims it's not a problem. I wonder.

i have a 2003 rav4. was making a rattling sound on the engine and it sounded like a diesel engine. everyone was sayimg timing belt and guides so i went ahead and changed it. started the car and the same noise. then i removed the VVT and the inside was broken. got a new one and replaced it, started the car and noise was gone. after 3 months, the same noise came back. do you know what is causing the VVT to break?

toyota dealer just repaired my 2009 rav4. TSB 0041-13. The spring loaded pin is not dropping in to lock it up at cold start. The rattle stops after oil pressure comes up to full. $625 repair at the dealer.

Pin locks the system when there is not enoug oil pressure. In example on engine startup.

Why did you replace this vvti gear because i have a 2009 corolla and when the engine is cold it gives me a loud rattle for like 3 seconds and the dealer told me it could be the vvti gear.

Sounds like oil starvation. Try changing the grade of oil you use to slightly thicker cold viscosity.

i have nissan, i wonder how often this camshaft damages? may we clean it or should replace it with new? thanks.

How many degree vvt open?

I work at the factory that machines the housing, rotors and the intake and exhaust sprockets you have there

the lubricating oil make the cam change it teeth, it will change when the RPM change too.. my brother tell me like that because he works at Toyota factory..

I think the ZR1 related to the engine number of those vehicles. I dunno though, this is all new to me, I'm just hoping to make a purchase on a 2005 corolla tomorrow, so was just looking into its engine, to get some idea of strength / what to expect / servicing etc. Thanks for the upload.

Both are right, old MIVEC on 4G69 engine for example is "like" a V-TEC but better, MIVEC on newer 4B11 engine is the same oil controlled VVT-i that Toyota uses but way more better.

Pin is actuated by oil pressure. It keeps the cam in the low rpm position when the engine isn't running

thank you very much for your video. very clear the vvt-I

suggestion for anyone trying to remove these odd shaped bolt heads. Just spot weld a washer on the head of the bolt. Then weld a nut on the washer. Now, very easy to move with a nut welded on top of the bolt.

Very clear explanation

I also have 2009 Corolla and I am experiencing the same start up noise. My question is does this problem also cause poor gas mileage and if its not fixed can it cause any serious problems?

orange blocks are oil seals?

Can you get these cams reprofiled for more power.

I have a 2zzge VVTL-i 03 toyota matrix whats the difference.

You might try synthetic oil if you aren't already using it, it will reach the top of the engine faster upon start-up. Over time, it might also clean out sludge that is slowing down the oil's movement. If higher quality oil doesn't help, then move on to hardware diagnosis via your mechanic.

Security torx. Common on many things like microwave covers.

That radio station your playing sure plays alot of ads

Nice video. That is the part that is messing up on my 2008 Highlander. For some reason now oil drains out of this area during a cold soak of at least 5 hours. When the car is started you get a rattle at start up. Sounds like crap. Only a $6,000 dollar fix from Toyota.(ha) Been doing this for the last 30,000 miles so it evidently isn't fatal initially.

I found out that they do make a tool to remove the cover plate on the VVT....its called a 5 point torx or 5 point star bit....comes in different sizes like torx. It can also be referred as a 5 point tamper proof bit but those usually have a hole in the end.

Can you drive Your Highlander with a damage timing chain guide

I have a 2007 camry 3.5 and i have a cold start rattle from time to time, is that pin that you took out the reason for the start up rattle?

Exactly, I mispoke. The cam gear itself is always in the same position, the cam itself is rotating.

reduces valve depth ??

Thanks, man. I appreciate the video and your candor! :-P

can you also take apart the exhaust timing gear. I would like to see how it looks inside