Fuel Injectors for 2001–2022 Toyota Sequoia

How long do Sequoia fuel injectors last on the 5.7L versus the 4.7L?

The 4.7L 2UZ-FE injectors typically make it to 130,000-160,000 miles before you see pattern failures. The 5.7L 3UR-FE runs higher pressure and tighter tolerances, so expect issues starting around 90,000-120,000 miles if you're in a hot climate or do a lot of towing. Flex-fuel 5.7L models can see earlier failures if E85 was used regularly, because ethanol is a solvent that accelerates wear on the injector seals. The 4.6L is rare but shares the 5.7L lifespan characteristics.

Can I replace Sequoia injectors myself or does this need a shop?

On the 4.7L, injectors sit under the intake plenum. You'll pull the upper intake manifold, disconnect the fuel rail, and swap them out. It's a 4-5 hour job with basic tools. The 5.7L is easier—injectors are on top of the engine under individual covers. You don't remove the intake. Just relieve fuel pressure, unbolt the rail, pull the injectors, replace the sealing washers and O-rings. Two hours if you've done it before. Torque spec on the fuel rail bolts is critical—15 ft-lbs, no more.

What codes indicate injector problems specifically on these Toyota V8s?

You'll see P0171 and P0174 system lean codes first, because the ECU detects one or more injectors aren't delivering enough fuel. Then come cylinder-specific codes like P0304 or P0307 as misfires develop. P0201 through P0208 are injector circuit codes—those mean electrical problems, not mechanical clogs. If you're seeing P0300 random misfire with no pattern, check for vacuum leaks at the intake gaskets before blaming injectors. The 5.7L also throws P0016 cam correlation codes when an injector failure causes rough running that confuses the VVT system.

Why does the 5.7L Sequoia get carbon buildup on injectors faster than other Toyotas?

The 3UR-FE uses port injection, not direct injection, but it runs a hotter combustion chamber because of the VVT-i system holding exhaust heat for emissions. That bakes fuel residue onto the injector pintles. Add in short trips where the engine never fully heat-cycles, and you get varnish deposits that restrict spray pattern. The 4.7L doesn't have dual VVT, so it runs cooler overall. Using Top Tier gas helps, but once you're past 100k miles on a 5.7L, the deposits are already forming.