First post, so sorry if anything isn't quite right!
Have an '06' GS300. Recently noticed mat in left rear footwell was wet. Mechanic put on ramp and checked underneath - no obvious problems. Removed mat, lifted carpet and insulation underneath was also saturated. Mechanic put it down to leaving window open in rain (usually check all windows before leaving car). Have been trying to dry it out but have now found front left footwell is exactly the same - wet car mat, soaking wet carpet and suspect insulation will be the same.
No sunroof, so can't be leaking from there. Right hand side is dry front and rear.
Does anyone have any ideas, please? I'm not mechanically minded but my husband is, so be as technical as you like!
Many thanks.