Gville350

iTrader: (10)

A Seafoam or like cleaner just won't be enough, like others posted. The carbon build-up is usually so bad that it needs physical persuasion in order to clean those valves.

Jeff Lange

iTrader: (1)

Many other DI engines have similar concerns, in particular BMW. Walnut blasting is quite common on BMW's, and as I said, isn't extremely expensive to get done. If you do it every now and then once there is carbon buildup, the car should run for many years and many miles without issue. Additionally, adding an oil catch can may potentially slow down the carbon build up as well.

Later IS250 engines have updated piston rings to help reduce blow-by, etc., and thus experience carbon build up at a lower rate. The Lexus TSIB/extended warranty for this concern involved updating the pistons and rings of earlier models to the newer type, this has now expired for most IS250 models.

I wouldn't recommend against buying an IS250 because of this issue. It is certainly a nice feature that most other Toyota DI engines have port and direct injectors, but as I said, it's a common issue with all DI-only engines in many cars and cleaning the intake valves is a pretty standard operation these days. Much like having to replace brakes or other maintenance/repair items.

Jeff

romeo1040

I have a manual is250 would it work for me