The 2014 Lexus IS350 reminds the driver that "injector maintenance" is required every 10,000 km.

Besides this advisory annoyance, as far I can tell there is no difference in drivability.

I don't think this is a case of Lexus being over-protective. The engine utilizes gasoline-direct injection, so I imagine that this message relates more to the high-pressure direct injectors.


  • What periodic maintenance do these direct fuel injectors need?
  • Is it out of the realm of a DIY-er to perform this maintenance?

1 Answer 1


So, the IS350 actually utilizes both port and direct injection. This results in the IS350 having fewer carbon build-up problems than the IS250, which exclusively uses direct injection.

The dealer/shop procedure for this maintenance is, at best, to inspect the valves for build up. If you want to maintenance the vehicle as recommended by Lexus, take it to the dealer and have them inspect it and perform their mfg recommended work.

In my experience, you would do better to simply run a can of injector cleaner through every 10,000 km. At 40,000-50,000 km intervals you will still need to take to a shop for a cleaning. At that time, if the shop sees it necessary, they will sandblast the valves with an abrasive material like walnut shells to remove remaining carbon build-up.

  • So is this more about the intake valves and less about the injectors themselves? That does make some sense, but then why don't other cars with regular port injection have the same 10k advisory interval?
    – Zaid
    Commented Aug 23, 2016 at 21:37
  • The gas and additives sprayed from port injectors passes through the intake valves, keeping them clean. Direct injectors spray directly into the cylinder. The gas never passes through the valves.
    – justinm410
    Commented Aug 24, 2016 at 11:00
  • 1
    I still don't see how this answers my question: what periodic maintenance do direct injectors need?
    – Zaid
    Commented Aug 24, 2016 at 11:51
  • 1
    Were you looking for me to tell you where to apply the dish soap and toothbrush? Run injector cleaner through your gas (which cleans the valves) and take it to a shop for inspection every 40-50k km. Gas injectors are replaced when they stop working, not cleaned or maintenanced. Carbon builds up in the valves, not inside the injectors.
    – justinm410
    Commented Aug 24, 2016 at 13:04

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .