Has anyone had a chance to actually inspect the intake ports and valves on a 2GR-FKS with D-4S? Curious how well it does with keeping intake valves clean. If this chart is accurate, it looks like you would have a "cleaner" engine if you drive slow and baby it than it would with hwy driving?
2GR-FKS ports & valves with D-4S
- Thread starter Johnny248
- Start date
Even if it's a highway only vehicle it wouldn't matter it'd still have plenty of time to clean the valves in the times you're slowing down to park/fill up and drive away to get back on the highway. Doesn't take much fuel to clean the valves.
I will have to do some more reading on how it works. Not sure if it automatically adds Port injection if you are stopped at a light, idle, etc. I've watched Idocars tear down quite few DI engines where the valves look terrible. If the Toyota system works well, it makes one wonder why more manufacturers aren't using something similar, other than it being an extra expense.
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Ford uses their own dual injection system in the Ecoboost and Coyote engines.
I took a quick glance at the intake ports on a 2GR-FXS(hybrid version) that saw 130K of hard Uber life. The ports looked like typical Toyota and I didn’t see a need to get them media blasted.
dnewton3
Staff member
Last fall I did a 100k mile service job on a friend's Tacoma with the 2GR-FKS. Sparkplugs, major fluids, etc. To do the sparkplugs, it was easier to remove the upper intake. Once off, we could see down the runners to the valves. They were in surprisingly decent shape; very little build up. They were not spotless, but certainly good enough for another 100k miles without major concern. I was pleasantly surprised. Bodes well for the D-4S system.
Elkins45
Site Donor 2026
Mazda’s Skyactiv engines seem to be a notable exception to this.
It's far less of an issue than it's made out to be.
There are millions of F150s ecos out there built from 2011 to 2018 that are DI only. They work fine and, outside of some early BMWs and VWs that had issues, most manufacturers figured DI out quickly. Ford has patents about valve timing that backwash fuel onto intake valves. I have 3 DI only vehicles (two are twin turbo) and none are known to have buildup issues.
for example:
https://patents.google.com/patent/US7137377B2/en
There are millions of F150s ecos out there built from 2011 to 2018 that are DI only. They work fine and, outside of some early BMWs and VWs that had issues, most manufacturers figured DI out quickly. Ford has patents about valve timing that backwash fuel onto intake valves. I have 3 DI only vehicles (two are twin turbo) and none are known to have buildup issues.
for example:
https://patents.google.com/patent/US7137377B2/en
The coyote family uses it, as well as VW/Audi, though they were primarily using it to reduce soot out the tailpipe. Once they moved to OPF/GPF they went back to DI only.
In my experience results are mixed, engines that see heavy, prolonged load do better regardless of whether they have secondary port injection and whether that takes place at low or heavy load. Of course PCV design also plays a role.
