MAB

99 RX300 w/78K miles

Already had throttle body removed to service IACV (please read my other thread) so I thought I would check-out the infamous 3 plugs next to firewall. Middle and driver's side completely accessible with throttle body removed. On passenger side, I removed two screws holding ACIS actuator bracket so I could swing it out of the way. Then removed PCV valve/hose. This provided easy access.

As expected, spark plugs looked great. Sharp edges and perfect gap. Threads were getting a little corroded so I dressed them up with anti-sieze and re-installed. Figure I will replace at 120k. By then I will likely need to service IACV again so little to no wasted effort.

Many posts re the difficulty of removing these plugs, but believe me it just isn't that hard.

Hmm lets see you removed the throttle body, removed the ACIS actuator bracket and removed the PCV hose. THEN accessing the spark plugs wasnt very hard!!

Point taken. I should have said, if you already have the throttle body removed for other reasons you can easily get two. And, it only takes a few minutes to remove ACIS bracket/PCV valve&hose to get to third.

I followed the instructions on this site http://mywebpages.comcast.net/rx300how2/index.html

and it worked out fine for me. Took about 1.5 hours total as those back 3 are a bit of a pain.

I didn't totally take off the PVC hose, just unplugged it on side that is next to the left side plug.

It helped alot as I didn't want to have to remove a whole lotta parts and I didn't have to following these steps.

Boy a busy day, cleaning IACV throttle body, spark plug replacement and oil change.

Glad to be done.

Thanks again to GoldenStateSilverSport. I am sure your procedure saved me at least $650 considering what dealers here in southern California charge for shop time.

For the benefit of other LOC members who may do this job in the future, I want to share a trick I learned about removing the VERY tight screws (phillips head).

I had tremendous difficulty removing these phillips-head screws (they are all the same size) => the 2 screws holding the coil on the IACV, the 3 screws holding the right throttle body and the 4 screws holding the IACV to the right throttle body. I tried tight-fitting screwdrivers, various phillips tips in a ratchet drive, vise-grips on screwdrivers, etc…but the screws wouldn’t budge. All I was accomplishing was damage to the screw heads.

I was about to give up when I thought of a damaged bolt remover tool (that uses a socket principle) I had seen advertised. My reasoning was that if I could find the correct size remover socket, that the tapered, spiral-flute sockets would fit over and grab the shoulder of the phillips-head screws. Then, I could apply enough torque to loosen them.

I found what I was looking for at Sears. I bought their part number 9-52161 (Craftsman “Bolt-Out”-Damaged Bolt/Nut Remover Set). I also looked at Sears part number 9-52154 (Craftsman “Screw-Out”-Damaged Screw Remover Set) but decided they would do more damage to the phillips heads. Bottom Line…9-52161 did a very nice job. The #4 remover out of this set engaged the shoulder of these particular screw heads well. Note: to drive the remover…I put the hex end of it in an appropriate size socket and used a ratchet wrench to drive the socket.

For those that have not seen them - these remover sockets have tapered spiral flutes inside them, which grab a damaged bolt head when they are turned counter clockwise and release the head when they are turned clockwise.

An afterthought - I was surprised to see these rather large screws in a phillips-head format. Seemed a really poor choice. I have never seen that in an American car…they use hex head instead. Yet, I don’t think this was a mistake because the Japanese designers are smart folks. Therefore, I wonder if the use of phillips-head screws in this application was intentional…to make it that much harder for non-dealer mechanics to work on? The use of these screws make a fairly easy disassembly and cleaning job WAY tougher. It would cause a lot of people to say, "I'll take it to the dealer".

By the way - I did take off the black metal piece mounted on top on the two throttle inlet holes that TunedRX300 asked GoldenStateSilverSport about. It improved access and visibility, which really helped when aligning and bolting up the right throttle body to the left one. I think it made the job easier, overall.

Best wishes to everyone. :D

Thanks TallGuy as well as GoldenStateSilverSport for the great instructions.

I did this job today and it was not to hard at all.

Only thing I would suggest is the same thing that Tallguy suggested in using the Craftsman “Bolt-Out”-Damaged Bolt/Nut Remover Set

part number 9-52161. Made it much easier removing the 3 very tight Phillips head screws that hold the right throttle body in place. I almost gave up until I bought this tool and it took the screws right out. The other 2 screws that hold the black coil to the IAC are a bit smaller than the 3 screws that are holding the right throttle body. I just used needle nose vice grip pliers to loosen 3 of the screws that hold the IAC to the right throttle body and the 4th I was able to get with a tight fitting phillips. Basically these 4 screws and the 2 that hold the the coil to the throttle body are the same size. The 3 that hold the right throttle body are slightly bigger in head diameter and this is were the #4 bolt out tool worked for me. It is to big for the other 6 screws ( 2 that hold black coil and 4 that hold IAC to right throttle body). Also there will be some coolant that leaks out when you take the throttle body out and the 2 hoses that attach to the throttle body. Not enough to worry about though. At least I didn't worry about it. Cleaning was a breeze and don't forget, as most have already stated the small wavy brass washer that sits in between the black coil and the throttle body when you reattach the black coil to the Throttle body.

Thanks again.

:cries: Now tackling the spark plugs on this beast. front 3 are a breeze the back 3 I'm gonna have to read the forum for suggestions. See ya......

Thanks mehullica. It was as you suggested small rubber hose back below the aircleaner box and by the Brake fluid resevoir. It was indeed disconnected. Thanks again for the help.

I have a 2002 Lexus Rx300 with 72K miles on it and the Check Engine Light (CEL) keeps coming on.

The code P0440 which is Evaporative Emission Control error code.

I have reseated the gas cap a couple times and cleared the code with my OBD2 code reader and it still keeps coming back. I recently installed a K&N air filter but don't know if that would have caused this problem.

Any other suggestion besides replacing the cap which seems to seal good as when I remove it you can hear the pressure release. I did have a couple other codes P0441 and another P044? but those have not come back after clearing the CEL the first time.

Thanks......