clubfoot

Most moder bay cars don't use freon, if I'm not mistaken. Did you change your cabin filter (glove box) before it stopped working?

With the hood open inspect the cabin air intake at the base of the windshield for debris like leaves etc. If nothing is blocking the cabin air intake follow the next step. With your AC set to AUTO and auto pass through,....turn off your car, open the glove box, remove the plastic parcel shelf (lift and pull out from the back and side). Slide up the black plastic panel at the back of the glove box which gives access to the cabin airbox and filter assembly. If the "white door" is down and you cannot see the filter assembly,... DO NOT LIFT the DOOR!!!! You can damage the mechanism!! Turn back on the power and operate the AC controls until the door raises! Once you have clear access lift and remove the filter and inspect for leaves or sucked in debris. Replace filter if scheduled,....usually once per year. Run the AC to see if you can hear the noise before putting everything back.

I don't think the OP is interested in acceleration and a slight speedo error but more with ride "softness". Come to think of it he probably should have gotten an ES,...but that's another thread. He may gain some quietness from an all season but he indicated the ride was too rough. So you're saying an 18X40 all season is allot quieter than an 18X40 summer tire! Did you change brands of tires in your conversion?

The 50/17 combo will give you the smoothest ride. don't worrry too much about the speedometer as it will not be too far off.

Then I would say the 17" wheel package for your model would be a very good compromise as it would have the smallest speedometer effect. The dealer may even offer you a straight swap as the 18" are more expensive.

Is your IS250 a sport package model? If it is you may have better results installing the "standard" model shock and spring package. If you can take a test drive in the same model year IS with the standard spring/shock setup then you will be able to compare.

From what they described in the recall letter the bolts could come adrift and fall into the engine,...

I guess it was a known trouble area, btw how many miles on your IS350? It's now at 180,000Km and the alternator died today :(

If you have the privacy screen, raise and lower it :)

Sewell Lexus IS parts.

I've had mine replaced twice already,...no big deal about six hours labour according to the previous TSIB.

Also try changing brands of fuel.

If I'm not mistake there was a Lexus TSIB issued for the sulphur smell.

Have you tried disconnecting the battery again for at least a half hour and reconnecting it?

Divide 61 by 8 = 7.625K miles per year.