sparks11

thanks lexmex, the process was really smooth and painless, took me about 1 hour and 30 minutes to complete the job, and I saved $180 labor that my local mechanic wanted to change the spark plugs, plus when I removed the pcv valve I realized it was bad and I replaced it as well.

willie83

I just did this today in about 2 hours. The most difficult part for me was releasing the electrical connectors from the coils on the back 3 plugs. I was never able to get 2 hands on any of them. I was also disappointed I could not get the vacuum actuator on the left side off. the Phillips head screws just wouldn't budge without stripping the heads. I have a bruise on my left forearm from that thing. But overall, not that bad of a DIY.

blaster30

I did this on Sat. Took about 1.5 hours. Dealership wanted $545.00 for the job.

I am happy that I didn't need any coil packs. The hardest one for me was the middle in the back.

Baetke

Blaster30,
How many miles on those plugs?

blaster30

There is 160,000 on the RX. I assume that they are original. I just bought the car about 6 months ago. Been great and this site has saved me so much..

I replaced AC servos, O2 sensors, PCV valve, spark plugs. And a new master key.

Next is the door actuators.

tarzan17

Thanks Lexmex for the great DIY. Changed the front plugs about two months ago and finally got around to changing the rears today.

I went with removing the cruise cable and PCV method. Found that a 10mm flex wrench came in handy to remove the bolts and a stubby ratchet made it easier for the plugs. To push the tabs on the connectors I used a small screwdriver (less than 3") to press the tab.

Also, I practiced with the two 3" extensions and 5/8" socket (not spark plug socket with gasket) on the front plugs as well as removing the connectors with two flat screwdrivers.

Was surprised on condition of rear plugs vs front plugs. The new front plugs I replaced two months ago had some black carbon on the ends and smelled of gas (expected them to look new). Also expected the rear plugs to have the black carbon and smell of gas but they did not.

bmwboyee

I know this is an old thread but I just wanted to say thank you. Was able to use this guide to change my plugs and coils. At first it was rather difficult but I think I could do this in less than an hour if I had to do it again. I actually had to replace the 1st coil as I didn't do that to begin with and it took me all of about 20 minutes. Thanks again!

P.S. for bank 3, I found it easier to work from the bank 5 side with my racket than from bank 1.

M45owner

Great writeup...these arent nearly as hard as my Q45 and M45 though.

ack300

Lexmex, thanks for the excellent write-up, I know these are time consuming things to do. I'll have this out there with me this weekend.
One suggestion on a spark plug tool - I bought a spark plug tool for a Dodge truck which has a long reach to the plugs - it was $10 at Advance Auto and is excellent and is a Gear Wrench 80546. On the tool, the socket extension is attached to the plug so you can pull on it to get the plug out, plus it swivels about 5 or degrees so that you can get the right angle on it or move the ratchet around to get more rotation. Also, the socket is magnetic so it pulls the plug out and put the new one back in easily. The magnet is pretty strong and I haven't dropped any plugs with it. If you Google the tool part number you can see a black band on the back of the socket; I thought it was the magnet first off but it's actually a textured part that allows you to get a decent grip of the socket with your fingers. And no, I don't work for Advance Auto or Gear Wrench, but I did just buy a 2003 RX300 a few weeks ago and am doing all these sorts of maintenance things to it now ( did the trans fluid filter plus pump through last weekend , well worth it ).
Thanks again Lexmex.

appsdba

Hey Guys,

I wanted to share with you the video below. I followed the same procedure to replace all six spark plugs on my RX300 and was successful. Even though this was done on a Toyota Sienna, the same procedure applies to our RX300s. Enjoy!

DewHawk

LexMex, Great instructions for changing plugs. The back 3 are as PIA as expected, but doable. My son and I completed in about 2 hours. What we learned: 1) Buy the 5/8" magnetic plug extensions for 3/8" drive ($35), 2) the suggestion to buy short ratchet ($10/$15) good idea, and 3) it was easier on the left and center back plugs if you leaned over the front of the car and using left hand left of manifold and right hand on the right side of manifold, especially if you are right handed.

Anyway, thanks a lot for the instructions and help!!

ASP20

Lexmex, Thank you so much for giving me the confidence and instruction to tackle this job myself. I just finished replacing all my plugs this past Saturday. I replaced them at what I believe is the recommended mileage 120k. I used NGK Laser Iridium Spark PLugs as replacements($40.65 on ebay). I took your advice and applied patience to the job. I did the job over four days. I replaced the front three the first day in order to find out what I was dealing with and to find out if I would be running into seized plugs or other obstacles. Fortunately none of my plugs were seized and everything went smoothly. When I replaced the plugs I dabbed a bit of anti-seized on the threads and started each by hand. I also used a well used spark plug socket to lower the plugs into the spark plug cylinder. The reason I used a well used spark plug socket was to be able to pull the socket off the plug after I got it seated and started in the threads. I then pulled the socket off the plug, removed the rubber hose in the socket and then tightened the plug the rest of the way. I tightened the plugs by feel(not torque wrench) and snugged them, but not over tightened. I found your removal of certain parts before trying to tackle the rear plugs to be essential. I was very careful to put all removed parts back just the way they were. I took my car for a test drive this past weekend and I think I am getting about 2 MPG better gas mileage and the car seems to have more pep. I am a shade tree mechanic(novice) and I would recommend this job for DIYers! Thanks again for all you do for this forum!!!!

Z07

I know this is an old post. But for people reading now...

That's because they aren't Phillips screws. They are JIS screws and when they are stuck need a JIS driver to turn without damaging them. Japanese Industrial Standard drivers can be ordered online easily and anyone wrenching on a Japanese car or bike should order a set of bits or drivers.

http://www.instructables.com/id/When...rial-Standard/

wing0

I see the list of tools required includes 12 mm wrench.
However, I don't see it listed in any of the steps.

carguy07

Do you have to disconnect the harness from the coils in the back to do the rear plugs?