I have a 2005 RX 330 with 1250,000 miles and decided to change the plugs, I searched the forum for procedures.
I removed the engine covers and the air filter and cover but I did not remove the upper intake part of the manifold, just the throttle body, nor did I remove the cowl, it took me about 2 hours to get the middle back plug out and replaced. It took me about 6 hours from start to finish and I took several breaks to rest my back from leaning into the work.
I changed all six plugs, used same Denso SK20R11 Iridium, cleaned the throttle body with cleaner and put all removed components back together and started the engine and it now idles at 1100PRM, where before it was around 600RPM.
Any thoughts on why the idle speed has changed?

 

I would check all hoses, maybe you have a vacuum leak.....

 

Reset, remove battery cable. Try it.

 

What plugs did you install?

 

mandyfig, I did try that, however, I only left it disconnected for a few seconds, I'll retry and and try a longer disconnect, thanks.
I used the Denso SK20R11 Iridium plugs.

thomas1, I checked them, but will go thru them again, thanks.

 

I am tackling this procedure in a few weeks. Any pointers? I plan to remove TB and upper intake. Any hidden bolts to be aware of?

 

mandyfig, I unplugged the battery and left it disconnected for about 35 minutes, and when I first started the engine after reattaching the battery, the rpm's were high - just under 2000 but after it reached normal operating temp, it setteled back to normal idle. It did not do this before when I only left the battery disconnected for about one minute, it was still runnng high RPM's after reaching normal temp. I assume leaving the battery disconnected for 30 minutes reset the ECU - I read that somewhere. I restarted a couple of times and it seems to be back to normal.
thanks!

 

alchemist, If you pull the air filter cover, filter element, throttle body AND the upper manifold - you should have no problems. I used a couple of bolts to plug the coolant lines while I had them disconnected and I cleaned the throttle body with spray while I had it off - other than that I just replaced the plugs.
I am still not sure why I had the change in idle speed, while i was cleaning the throttle body, I did move the butterfly to clean it and I wonder if that upset the position on that device??
I did try to remove the upper manifold and had all bolts off on the front but could not get it to clear the two outer studs when I tried to lift it - the studs have a reverse torx head and I did not have a torx socket to remove them. It did feel like it had a hidden bolt on the back side but I used a mirror and colud not see what was holding it. Maybe someone else can answer about a back side bolt. I will say this, I replaced the steering rack on this car and that whole process was much easier than the middle back plug replacement.
Good luck and if I can help, just ask.

 

Very good to hear.

 

In case you haven't done it, you will need to reset all the windows, moonroof and rear hatch.

 

And your radio stations...

 

I am glad you sent the reminder,,,,I reset all items - except the moonroof. I'll do that now, thanks.

 

I'm planning to do this soon.

To Grumpy: Would the right torx socket have made this just a lot easier? In other words, were you to do this again, would you be sure to add that socket to your arsenal?

For those that have removed the upper manifold, is there a gasket requiring replacement? Or can it be reused? Just a compression gasket..i.e. no sealant / adhesive?

My 2005 is approaching 140,000 on the original plugs, and I plan to replace with the OEM plugs as Grumpy did.

Thanks,
Jeff

 

Good info thanks. I will keep an eye out for this.

I have been told both - meaning you can reuse. I purchased new the gasket that goes between the upper manifold and lower and the gasket that goes between the upper manifold and TB. They were inexpensive so I just broke down and got them off rock auto. No sealant or adhesive. Look for 'plenum gasket'...

http://www.rockauto.com/catalog/more...159&cc=1432806

 

Formula271 - I could not determine if there was an unseen bolt on the back that was locking the plenum in place. I could lift the front but could not clear the top of the studs, I am making an assumption that if the studs were removed I could remove it, BUT it seemed like it was being held by something on the back side???
Without removing the plenum I had to reach my left hand around the left side and my right hand around the right side facing the engine but could not get a thumb and finger on the plug, so I used one finger on one hand and one on the other and that was the best I could do to get my socket and extensions and rachet on,,,and I could only get one rachet click at a pull. Once it was finger tight, I put a piece of tubing on the plug and twisted until I could pull it out and I used the tubing to put the new plug in and get it started so as not to cross thread it. It would have been much easier with the plenum out of the way. Rockauto has good layout and prices for the gaskets.
After I had finished I was telling my oldest son about the job and he said - Oh I have a set of the torx sockets,Dad,,,,I thought to myself, now he tells me. If I do it again I would get the socket and try it. I don't have a long handle 3/8 rachet handle, I have the Lowes rachet that the handle twist the socket and extends but it was too large to get a pull, I had to get the plug to break loose with a standard 3/8 socket and a steady pull.
Good luck