04 Rx330 Spark Plug Replacement

[KBRX330]

Well it's done. You can replace the plugs on your RX330 without removing the engine. ( I ran mine 140,000 miles)

Parts needed:

6 iridium plugs. Mine spec'ed Denso 90080-91180 that I got from a Toyota dealer for $10 each (Lexus wanted $14)

Note: do not gap the plugs as you will ruin them.

1 PCV Valve

1 Air Filter

1 Can throttle body cleaner spray

1 quart coolant

1 tube permatex anti-seize (small)

1 tube blue loctite (small)

Tools needed:

1 3/8 flex head ratchet

1 3/8 regular ratchet

1 5/8 spark plug socket

1 6" 3/8 socket extension

1 10" 3/8 socket extension

1 10mm 3/8 socket

1 12 mm 3/8 socket

1 5mm allen head socket

1 10 mm open end/box end wrench

1 19mm open end box end wrench

1 pair of pliers

1 pair needle nose pliers

2 phillips screwdrivers (1 long 1 short)

2 flat bladed screwdrivers (1 long 1 short)

1 piece of rubber tubing 8" long that will fit snugly over the top of the spark plugs but still pull off.

1 pack of stick on labels & sharpie marker

1 trouble light

1 small wire brush

3 shop rags

All instructions are oriented to be facing the engine (battery on your right)

ENGINE MUST BE COLD

Remove black cover (4 push clips) and put to the side.

Remove the silver engine cover 3-5 mm allen nuts ( note the nuts screw over studs so be careful to lift the cover easily) There is a spring clip underneath the cover ( right beneath the Lexus logo) that pulls up an off. There is nothing to detach as it pulls straight upward. Put cover to the side being careful not to lose the allen nuts.

You will now see the front bank of plugs. Do one at a time. Remove 10mm retaining nut on coil. Unplug wire connector from coil. Wiggle the coil by turning slightly to break it loose form the plug. Pull upward and the coil & boot assembly will come right out. Using 3/8 ratchet & long extension break plug loose and unscrew a few turns until it turns freely but do not remove plug. Remove ratchet and slide rubber tube over end of spark plug and finsh removing the plug.

(Note: I removed the rubber insert form my spark plug socket for fear of having it stick to the spark plug inside the plug well.)

Coat new plug threads LIGHTLY with anti-seize and use rubber tube to get the plug started back in so as not to cross thread. Tighten with 3/8 ratchet ( you can torque the plugs on the front but don't expect to on the back side). Re-install coil and wire clip and 10mm retaining bolt

Repeat for other two front plugs.

YOU ARE NOW 20% DONE :-) Take a coffe break The real work is just ahead.

Remove air filter top cover and set to the side. Number each rubber hose and connection point with labels for ease in re-assembly.

Remove ALL air intake hoses & plastic pieces in front of throttle body. Number hoses & connection points again

Unclip electronic plug from front half of throttle body and push out of the way. Remove all hose connections to throttle body. Two are coolant lines so you will lose some coolant (put a rag under the open hose ends as they will continue to drip) Label all hoses & connections.

Remove front half of throttle body (4 bolts) and place aside (label bolts)

Remove the throttle body bracket bolt on the back half of the throttle body (1 bolt)

Remove back half of throttle body (4 bolts) and place aside (label bolts)

Remove PCV hose & unscrew PVC valve & remove (discard)

YOU NOW HAVE ACCESS TO THE REAR BANK OF PLUGS... (this gives new meaning to the term reacharound :-) )

When replacing the rear plugs do not disconnect the wires from the coils or you will have difficulty getting them back on. If a coil tube assembly is stuck use the long flat bladed screwdirver to GENTLY pry upward on it. It will come loose. You will have to push them out of the way to R&R the plugs. There is not a lot of room to work but it can be done if you are patient. This where the rubber tubing is a lifesaver and be sure to use anti-seize. I was able to get the driver side plug & middle plug form the drivers side and the passenger side plug from the passenger side. If there are vacuum hoses in your way remove & label.

Clean throttle body ( do not spray the black electronic plug on the front half)

Install new PCV valve

Install new air filter

Re-install everything in reverse order using loctite on the throttle body bolts.

The new PCV will come with sealer on it. If not use loctite.

Re-fill coolant

Test drive

NOTE: The Haines Manual says you need to remove the plastic intake manifold. NOT TRUE.

Good luck!

[Liu_RN]

Good info. Wow that's alot of work just to change the spark plugs. I sure hope I don't need to change my plugs for a long long time. Hey Lexus, some of us owners like to do maintenance on our own cars. Wonder how much dealers charge for changing plugs?

[newtoncd]

It was $189 (for the 6 Iridium plugs and labor) at the independent shop I use.

[KBRX330]

It was $189 (for the 6 Iridium plugs and labor) at the independent shop I use.

That is super inexpensive. I would have driven to Denver for that one... The dealer here wants $400+

[KBRX330]

Good info. Wow that's alot of work just to change the spark plugs. I sure hope I don't need to change my plugs for a long long time. Hey Lexus, some of us owners like to do maintenance on our own cars. Wonder how much dealers charge for changing plugs?

It is a lot of work for plugs. But I did do the PCV valve replacement & TB complete cleaning which is important as well. The fuel economy on the car is definitely up as is the performance. So it's worth it. If you are pricing this service don't forget to add the disassembly & complete cleaning of the TB and PCV replacement. This total service at a local dealer here would be over $500. My cost was about $80. So, you are saving about $100/hr.

[fatmaxxv]

Good info. Wow that's alot of work just to change the spark plugs. I sure hope I don't need to change my plugs for a long long time. Hey Lexus, some of us owners like to do maintenance on our own cars. Wonder how much dealers charge for changing plugs?

It is a lot of work for plugs. But I did do the PCV valve replacement & TB complete cleaning which is important as well. The fuel economy on the car is definitely up as is the performance. So it's worth it. If you are pricing this service don't forget to add the disassembly & complete cleaning of the TB and PCV replacement. This total service at a local dealer here would be over $500. My cost was about $80. So, you are saving about $100/hr.

KB,

If I drive up to Ohio, would you do mine for free? Then again gas is more than $4....hmm.. :(

[lastplace]

Thanks for the info,

How often should the plugs be done?

[RX in NC]

I changed the Denso iridium plugs myself in my wife's previous 2000 RX300 AWD in October 2006 at 120,000 miles primarily because I knew that I would be selling that lousy vehicle in early 2007, and spark plug change jobs on these damn RXs are a major pain in the !Removed! to do (not to mention expensive if you have to pay a shop to do it for you)....

The original factory plugs still performed flawlessly and looked very good at 120,000 miles. They would have easily gone 150,000 miles and I wouldn't be surprised if some folks get close to 200,000 miles out of them....

Both Denso and NGK make superb iridium plugs. If you replace them prior to 120,000 miles you're just wasting your money. But that doesn't excuse you from pulling a couple of the front plugs (easy to get to) every 40,000 or 50,000 miles simply to take a look at them to ensure they're still in good shape....

[KBRX330]

I changed the Denso iridium plugs myself in my wife's previous 2000 RX300 AWD in October 2006 at 120,000 miles primarily because I knew that I would be selling that lousy vehicle in early 2007, and spark plug change jobs on these damn RXs are a major pain in the !Removed! to do (not to mention expensive if you have to pay a shop to do it for you)....

The original factory plugs still performed flawlessly and looked very good at 120,000 miles. They would have easily gone 150,000 miles and I wouldn't be surprised if some folks get close to 200,000 miles out of them....

Both Denso and NGK make superb iridium plugs. If you replace them prior to 120,000 miles you're just wasting your money. But that doesn't excuse you from pulling a couple of the front plugs (easy to get to) every 40,000 or 50,000 miles simply to take a look at them to ensure they're still in good shape....

When I did mine at 140,000 miles they were looking a bit worn but still functional for sure and would have gone 150k easily. Replacing them before 120k is a waste for sure. But I don't think going past 150k is good either. Their perfomance degrades so slowly you barely notice it. The tips on mine has some deposits built up which is expected but robs fuel economy by 2-3 mpg. You really notice the difference once you clean the TB & install the new plugs.

[KBRX330]

Good info. Wow that's alot of work just to change the spark plugs. I sure hope I don't need to change my plugs for a long long time. Hey Lexus, some of us owners like to do maintenance on our own cars. Wonder how much dealers charge for changing plugs?

It is a lot of work for plugs. But I did do the PCV valve replacement & TB complete cleaning which is important as well. The fuel economy on the car is definitely up as is the performance. So it's worth it. If you are pricing this service don't forget to add the disassembly & complete cleaning of the TB and PCV replacement. This total service at a local dealer here would be over $500. My cost was about $80. So, you are saving about $100/hr.

KB,

If I drive up to Ohio, would you do mine for free? Then again gas is more than $4....hmm.. :(

At $4 gallon it would be cheaper to have your dealer do it....... :D

[TXRX330]

Great Instructions! I think I'll wait until 140,000 miles. My 04 has only 78,000 on it now! Thanks KBRX330!

[code58]

Great Instructions! I think I'll wait until 140,000 miles. My 04 has only 78,000 on it now! Thanks KBRX330!

TXRX- You're barely half way to replacement time. I changed my DIL's (at 97k) and if I had pulled a couple of 'em before I bought the new ones I wouldn't have touched 'em. My judgement, I would say they are good for at least 150k. I believe in checking things on a regular basis but those plugs just refuse to wear out. In my estimation I wouldn't use anything but NGK or Denso (Iridium).

[smooth1]

Nice bump though. I'll add this to the How to's .

[KBRX330]

bump

[krayzielilsmoki]

just finished this... wow! the throttle body was insanely difficult to remove because all the screws strip easily so I just left them in place and removed the 3 back bolts and there is a rod attached to it with a bolt on the top and bottom, the top was impossible to get to so I just did the bottom. and there is one more 10mm bolt in the back that I had to undo before I could pull that out and get to the spark plugs. Thanks for the info this thread really helped