You might be familiar with the infamously carbonaceous 4GR-FSE featuring the GDI-only injection system.
I purchased my IS250 in 2014 with 107K on it and to my shock, learned of the GDI issues later (yes, shame on me for not doing better due diligence).
However, a top end inspection (through the lower intake by yours truly) showed only minor/normal varnishing and nothing at all like the horrific sludge farms you'll see on some of these engine and in the service bulletin that led to in some cases entirely new long blocks under warranty. This is the rare 4GR that seems to be OK on carboning up the top end.
It's been nine years, I'm at 176k now and still haven't incurred any notable carboning issues that I can tell. (I haven't been in side the top end however since I bought it). Oil consumption is too low for me to notice, which likely explains the cleaner-than-normal top end. I do notice periodically a throttle hesitation that Seafoaming the intake seems to resolve temporarily.
Since I took possession, I'd been given a diet of mostly PUP or PP in 5w30 or 10w-30 and OEM filters.
I just performed a 176k OC with PP 5w-30 and one quart of HPL cleaner and switched to the M1 EP filter.
I'd be interested in switching entirely to an HPL lube oil to help clean the engine and perhaps maintain such but I'm unsure which to use. Also, since the carboning up of these engines has a LOT to do with oil selection (and blowby) I'd like to stick with an oil that keeps the ring pack as clean as possible.
I'm not obsessed with pushing the OCI as far as possible, and cost isn't a huge consideration I'm willing to pay for a premium oil that keeps this car in top condition so that it will rust out long before it wears out.
In my location, winter temperatures rarely drop into single digits Fahrenheit, with typical winter overnight lows in the teens or 20s-- we don't get severe winters by my standard (calibrated by a childhood in North Dakota and Wisconsin).
Conversely, we don't get summer temperatures over 40C/104F very commonly either.
The car is generally *not* garaged, and the main duty cycle is a cold-start before a 35 minute commute in the morning followed by that same event in the evening returning home. If the engine is warm from my return commute, I'll often run errands in it that are small city mixed driving. Hwy vs City mileage split is about 80/20 but by time it's probably closer to 60/40 still favoring hwy. The car gets about 27mpg in this mixed use, with 25 in the city and 32 on the hwy. I generally buy fuel at Sam's club and do not use premium (I never have any knocking or evidence of octane insufficiency).
I purchased my IS250 in 2014 with 107K on it and to my shock, learned of the GDI issues later (yes, shame on me for not doing better due diligence).
However, a top end inspection (through the lower intake by yours truly) showed only minor/normal varnishing and nothing at all like the horrific sludge farms you'll see on some of these engine and in the service bulletin that led to in some cases entirely new long blocks under warranty. This is the rare 4GR that seems to be OK on carboning up the top end.
It's been nine years, I'm at 176k now and still haven't incurred any notable carboning issues that I can tell. (I haven't been in side the top end however since I bought it). Oil consumption is too low for me to notice, which likely explains the cleaner-than-normal top end. I do notice periodically a throttle hesitation that Seafoaming the intake seems to resolve temporarily.
Since I took possession, I'd been given a diet of mostly PUP or PP in 5w30 or 10w-30 and OEM filters.
I just performed a 176k OC with PP 5w-30 and one quart of HPL cleaner and switched to the M1 EP filter.
I'd be interested in switching entirely to an HPL lube oil to help clean the engine and perhaps maintain such but I'm unsure which to use. Also, since the carboning up of these engines has a LOT to do with oil selection (and blowby) I'd like to stick with an oil that keeps the ring pack as clean as possible.
I'm not obsessed with pushing the OCI as far as possible, and cost isn't a huge consideration I'm willing to pay for a premium oil that keeps this car in top condition so that it will rust out long before it wears out.
In my location, winter temperatures rarely drop into single digits Fahrenheit, with typical winter overnight lows in the teens or 20s-- we don't get severe winters by my standard (calibrated by a childhood in North Dakota and Wisconsin).
Conversely, we don't get summer temperatures over 40C/104F very commonly either.
The car is generally *not* garaged, and the main duty cycle is a cold-start before a 35 minute commute in the morning followed by that same event in the evening returning home. If the engine is warm from my return commute, I'll often run errands in it that are small city mixed driving. Hwy vs City mileage split is about 80/20 but by time it's probably closer to 60/40 still favoring hwy. The car gets about 27mpg in this mixed use, with 25 in the city and 32 on the hwy. I generally buy fuel at Sam's club and do not use premium (I never have any knocking or evidence of octane insufficiency).