2JZ Valve Cover Gasket and Spark Plugs: Lexus GS300 and IS300

2JZ Valve Cover Gasket and Spark Plugs:  Lexus GS300 and IS300

Here’s a step by step tutorial on how to replace the valve cover gaskets, spark plugs and spark plug wires on a Lexus GS300 or IS300 with the 3.0L inline 6 2JZ-GE engine.

Leaking valve cover gaskets are a common problem as vehicles age. On this Lexus GS300, the valve cover gaskets were leaking so badly that the spark plug wells were filled with oil and gunk.

Since the intake and throttle body have to be removed to do this job, it is also recommended to change the spark plugs and spark plug wires while they are easily accessible.

The procedure consists of first removing the engine covers and air intake tubes. A few electrical connectors and vacuum hoses must then be disconnected from the throttle body, along with the throttle cable. Be sure to label all connectors and hoses that have been removed for easier reassembly. The intake and throttle body is then removed as one assembly.
The use of a ratcheting wrench is recommended when accessing intake plenum bolts.

Once the intake is out of the way, the wiring harness must be freed from both sides of the valve cover and the ignition coil pack connectors removed. Usually the coil pack connectors have a tendency to break and should be replaced if they do. The wiring harness is also very brittle from the engine heat cycling over time.

Next, the ignition coil and wires can be removed. Make sure the spark plug tubes and area between the covers has been thoroughly cleaned before unbolting the 6 10mm bolts and 2 10mm nuts holding each valve cover on.

Wiggle the valve cover to break it free and work it around the engine harness and heater core hose. Clean all mating surfaces with brake cleaner and a lint free rag.

A Fel-Pro gasket was used to reseal the valve covers. For some reason it came with two driver side gasket and one passenger side gasket. Permatex black RTV was used around the “half moon” cam profile of the valve cover to aid the gaskets in sealing the corners.

The ignition wiring harness was then swapped over to a new one from NGK, and the spark plugs were changed for fresh new Denso double electrode plugs. It is important that double electrode plugs be used since this engine uses waste spark ignition, which means three coils power six cylinders.

Once the spark plugs, ignition coils and wires have been replaced, the intake system can then be cleaned using throttle body cleaner and then reinstalled onto the car. There are a number of vacuum hoses under the intake plenum that may take a while to reconnect.

A new plenum to throttle body gasket was used. Reinstall the plenum nuts and bolts, as well as the throttle body bracket on the passenger side of the engine, reconnect the coolant lines and electrical connectors.

Start the engine and let it warm up. Degrease the engine if it is oily and dirty, and take it for a long drive, stopping periodically to check for leaks.

The car will now run smoother and more responsive with the new plugs and wires, and won’t leak and burn oil.

Reference video:

Here’s the full write-up and discussion:




Bilalh Kenyatta says:

Very well done video!! You guys rock!! ^_^

Robert Greatsinger says:

Great videos, love backyard eco sounds and no dumb language or music-ic-ic-ic……Lord Jesus bless you with eternal salvation, eternally BETTER than car repair which is always needed until the DAY OF THE LORD.

Strong Suresh says:

You make it look easy. On my gs 430 the valve cover gasket started to leak. I gave it to my mechanic to fix. If you are inexperienced, do not try this kind of job on your own. Leave it to the experts. To the mechanic who made this video, you are definitely a pro, I would definitely bring my car you to fix. Are you in Ontario? How could someone get in touch with you,?

Cisco Talens says:

Where you live? How much to do mine exactly the video 1:1?

Minty Integra says:

Most detailed DIY job I've seen on youtube!

Fauna Valentine says:

All the brackets on my ignition coil wires broke, can I do without them?

Terphog420 says:

Where u at? do my car

srghrgtny says:

Dude if you use oven cleaner to clean metal parts it's gonna give you better results. But be careful with the painted parts because it's gonna take the paint off. I use it to clean the the back wheel of my 750cc because of the all oil I have. Just an advice for you to take if you want.

Kenneth Edwards says:

Can you fix my car

Jonathan Quach says:

Thank you so much for showing us how to replace the broken clips!!! I didn't realize I had 2 that was broken and after seeing this video, went straight to EBay to order mine! I just got done replacing them and the amount of accomplishments and satisfaction I have now is so great!!! Thanks again!!!

Delacey Brown says:

Any chance you know the part number for the studs?
While tightening the bolts and 4 nuts/studs, I broke 2 bolts and one of the studs. I found the part number for the bolts, but the diagram I was looking at for stud part number must have been wrong and Lexusparts sent me studs that are like 1/3 the correct length.
And of course no auto parts store knows or has them.

Thanks in advance, and great video!!!

peaceand love says:

Where does the vacuum hose at the
:34 second mark connect to. I have a 04 gs300 bought new resonator. The old was broken and didnt have hose.

MR Worldwide says:

Can you use oven cleaner??

jerry ulcek says:

Fantastic job my friend. As complicated as the valve cover replacement is on a gs300, your video from start to finish makes it possible for a novice mechanic to take on the job and easily save $500. Excellent video.

ZACKZAR33 says:

I did 75 inch pounds for the valve cover bolts and one snapped

Richard Morales says:

What if the ignition coil's blue rubber comes off and stays on the spark plug?

robmoran820 says:

How do you replace a coil boot for a 06 Lexus gs300?

Terry Reese73 says:

Whats a good estimate timeframe on doing this? I just picked up a 2000 GS300 and need to swap cover gaskets.

Gary Garibyan says:

Are the valve cover bolts all the same? Dealer is giving me 2 different part numbers, short and long. 91631-B0630 and 90119-06672

Pastor-Evangelista Marcos Sandoval Jr. says:

Great video! Keep up the great job!

Maurice Riley says:

I’ve watched this video at least 40 times. I appreciate the upload a lot. Just finished doing mine on a is300 though.

Rogelio Vargas says:

Is this the best or only way to replace the pcv valve?I’ve tried it from the top but being on there for 18 years the plastic is hard and I’ve broken the top of it.

supra _ boii88 says:

I love this video this video really helped step-by-step it was really easy and literally took the time of the video is the time I’ve got done also thank you so much for posting this it was really helpful if you have more 2jz videos

Richard Feliciano says:

I did the whole thing with this video, you made it look way easier than it really is though! Thanks brother

Daniel El-Aawar says:

On all 3 coil pack connectors, do the whiteish brown pins go in pin 1 slot?

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