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How do I Inspect Intake Valves Without Removing Intake Manifold?

Is it possible for me to inspect my intake valves without removing my intake manifold? Could I for example use a borescope camera and go through the PCV inlet on the intake manifold and maneuver it around to see the intake valves? Or do I have to remove my intake manifold? I’m trying to avoid doing so because I don’t want to have to replace the gasket. I’ve heard you should replace your gasket every time you remove the manifold, even if it’s not leaking?

Does anyone have like a video showing how you inspect your intake valves with a borescope camera. Like not footage of the valves, but actually showing how to move the camera around without taking the manifold off.

If this is your 15 year old Camry with 150000 miles why bother . If it does not have a problem why go looking for one.

Well I was hoping to keep the car a bit longer. I don’t have any problems and want to keep it that way. I was thinking of maybe using something like seafoam or something if I saw lots of carbon build up.

The gasket is $4.53 on rock auto. It’s ridiculous to not just pull the manifold and change the gasket.

You will have to remove it to replace all the bolts with non rusting ones, just check them at that time.

Just use Texaco or Chevron gas, or add a bottle of Techron to your gas tank for a couple tanks of gas.

Plenty of videos on YouTube showing manifold examination with a boroscope right down past the throttle plate. Just block it open and insert the scope.

If this is not a direct injection engine, it likely is not a problem. If it is, it couldn’t hurt to use intake cleaners anyway. There are videos on that, too.

Even a cheap borescope is many, many times more expensive that the gasket. Don’t fix what is not broken. I understand doing preventive maintenance but don’t go around taking apart things that usually last the life of the car unless you have reason to suspect them.

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No need to do this. You don’t have a direct injection engine, so you very likely have no problem with intake valve deposits. Go to Walmart and run a bottle of Techron in your gas tank once a month for a few months, if you’re concerned.

Much more likely you’ll cause a problem, than fix a problem, if you start monkeying around with the engine.

I have the 2AZ-FE engine which I thought was direct injection?


definitely not direct injection

Nope, only some of the very newest Toyota engines have direct injection.

I see . Thanks. Why would newer cars be directed injected. Kinda like going a step backwards?

That engine has fuel injectors in the intake ports, that is different from direct injection which has injectors that spray into the combustion chamber.

With that many miles there is going to be carbon on the valves but not enough to cause driveability problems that are seen on direct injection engines.

If you’re concerned about carbon build up causing valve-closure problems I’d probably start with a cylinder leak down test. That’s relatively easy for a shop to do & will tell you if any of the valves are sticking slightly open or otherwise not sealing properly. I’m not familiar with that engine’s configuration, but on my Corolla I think it would be possible to visualize the valve-stem area and possibly a portion of the top of the intake valves from the intake manifold. It would require a long enough and maneuverable enough bore-scope device of course to see them all.

If you fuel your vehicle with Top Tier gasoline, and the Check Engine light doesn’t come on for a misfire code, don’t worry about it.



??? It’s a lot harder to make a direct injected engine. The fuel injectors have to handle the pressure and temperature of the combustion chamber.

Toyota combines both kinds in its latest engines, partly to combat intake deposits, I think.


I think the motivation for using direct injection is improved mpg and performance. And there may be some emissions improvement too.

Right I think some of the newer Toyotas have what they call dynamic force which is a combination between direct and port injection. But I think the Yaris is strictly direct injection into the combustion chamber? Is this really the case, yikes!


Listen to the many posters who tell you to leave it alone. Removing intake manifold gaskets will likely result in particle falling into the engine, ruining the main bearings and the entire engine.

If you want to do a leak-down test, and that will tell you if any valves are sticking open or not sealing correctly, as per George_San_Jose1 advice. I don’t think you need to do anything as you’re having no problems with the running of the car, correct? If you want to spend money for a leak-down test, it better be at a garage that you know is totally honest; otherwise they can tell you anything

Whatever you do, DON’T tear into the engine, or you’ll regret you ever did, because if any type of debris gets inside - bye, bye engine. Removing intake manifolds requires meticulous cleaning of everything around the entire area. And then, if you change the gasket, you’ll have to be as meticulous as possible, with totally lintfree, special towels to carefully place in the open space of the engine after taking the gasket off.

Just leave it alone, and drive it!


FWIW Direct injection allows virtually any engine to produce more power. Everytime a manufacturer moveed to direct injection, the rated power went up. Why? Better combution control. The injector can fire several times in a single stroke, valve open or not. Finer fuel droplets that burn more efficiently. Compression ratios can be increase for greater efficiency and power because of the cooling effect of squirting liquid fuel into the cylinder. Lots of advantages.

Diesel engines grew much more powerfull and cleaner when they went to direct injection 20+ years ago. Car, truck and Semi tractor diesels.