Does anyone know when to change Iridium spark plugs on RX330?
It has about 40K and engine idling sound somewhat rough to me (idling at 700K RPM).

Also, do I really need to adjust drive shaft bolt? It’s recommended on owner’s manual and I don’t know what that is or how to torque in factory spec.
I really like to learn and I’ve all proper tools including torque wrench.

 

I believe that information is in the Owner's Manual under the maintenance schedule. Do you have one? I will look at my manual when I get home.

Gary

 

Just relating an experience with my RX300, with regard to the drive shaft bolt, when I used to take it to Lexus (more than 2 years ago), I would ask for this, but concluded no adjustment necessary. My uncle and I have looked at in the past 2 years, and also came to the same conclusion. I don't have the torques off hand, but I remember when he and I tried, no difference.

With regard to the plugs, the EARLIEST I ever see this done is at 60K. I did do it, but late last year I switched back over to TorqueMaster Plugs (I am over 100K now) and found that my Densos were quite dirty (we had high sulfur fuel down here). The best way is to take one of them off and see what accumulation/color is there.

 

Can anyone comment on this driveshaft bolt. This is a new area for me and I would like to know what it is, what it does, and what is involved in adjusting it.

Thanks in advance.

Gary
05 330

 

Just replaced the plugs on my '04 RX330 with 45,000 miles. I installed Denso Iridium Power plugs and I can't believe the difference vs. the OE NGK Iridiums. My acceleration is much better, like a smooth rush of power. Too early to tell about the fuel economy but I bet that improves also.

 

That would be the drive-shaft (propeller shaft) for AWD vehicles. The thing to do would be re-torquing the flange bolts.

Salim

 

Salim, I am guessing you are a REALLY slow reader? My post was 15 months ago.

Seriously, thank you for the input. I know what the driveshaft is but this is the first vehicle I have owned that asked for an inspection and possible retorque of the bolts.

From my reading in the past year, I can see that this isn't really necessary except for a periodic visual inspection.
Gary

 

I do the same thing sometimes when I have replied to posts without realizing they are old, usually in the course of searching for something.

With regard to retorquing, I haven't seen this necessary at all each time I have checked them.

 

I did not even look at the date

Some how the thread got marked unread since last time I was here.

I am so dependent on "unread bold ... moved to top of the list"


Back to your question:

There is always a good reason for manufacturer to recommend something.


Salim

 

When to change plugs is around 40-60k depending on if your a professional race car driver or a 60 year old lady. Also depends on gas quality. Since your seeing rough idle just change then plugs. SITCK with NGK, and get fuel system cleaner.

 

That seems way early in this day of electronic ignition and Iridium spark plugs as a blanket generalization. The maintenance manual says to change at 120K. I might go as early as 90K but unless you are running rough, like the original posted indicated, there is no reason I see to change at 40K-60K.

As a habit I do pull several plugs every 30K to look at engine health, however, that is another story.

 

I had ours changed at 93K in my wife's 04 RX330 and visually they looked to be in very good shape. I was getting the timing belt and water pump done at the same time, so I just had the entire package taken care of.

 

I installed DENSO Iridium Power plugs in my RX330 last week at 44,000 miles. They are fantastic plugs! Increased horsepower and fuel economy. They are a performance plug however so they should be replaced after about 30,000 miles. If you want more mileage than that, go with the DENSO Iridium Long Life plug, those will last 100,000 miles.

 

How much MPG did you pick up? And how much HP? Did you put the car on a test bay? Or it is all by "feel?"