Just wondering since someone awhile back did this to their IS injectors since they didn't level out the same amount. Does techron every 5k clean the injectors or do you need to take them out and have a shop do this? Btw I have had some slight idle hesitations but it could be my throttle body needing cleaning.

 

IS 250 or IS 350?

IS 250 has direct injection only and the IS 350 has both direct injection & port injection.

 

Injector cleaning is the LAST thing I'd look at for that issue. Assuming it is a IS250, first would be the usual carbon build-up issue on the valves.

 

Old standby is the "Italian Tune Job" where, from time to time, you go up a freeway ramp under wide open throttle to shake off the carbon deposits & such. Be sure you are at normal engine operating temperatures -- never for a cold engine.

 

Mines a 350

 

I did it on my 250 and the replacement o-rings and seals are very expensive. You also need a special tool to set the nylon seals on the DFI injectors (I have one for sale if you are interested).

I would try techron for a while. I had an old Camry that I drove to 270k miles. I ran techron or Chevron fuel quite often in that car. I had an issue come up and I thought it was the fuel injectors. I pulled them and had them bench tested. They were all flowing 100% rated output. I was the original owner of that car and always used better gas so I don't know how much it will correct an established issue.

 

I use Techron 3 to 4 times a year as the seasons change. I also was clocking 17k miles a year. That will drop with the additional vehicle and 4 mile commute vs 28.

That said, I'd start with a MAF sensor hose down. Repeat it like 4x back to back. Engine off, disconnect the sensor, remove 2 screws and hose away from all angles. Wear goggles as it can spray back.

How old are the plugs and does it get opened up occasionally?

 

The throttle body is electronic controlled so it doesn't need cleaning. I was talking to a mechanic that has worked on Toyota/Lexus for over 20 years and he told me they go bad before they need to be cleaned. I would first try two treatments back to back with Chevron Techron fuel injector cleaner, lots of full throttle to clean stuff out. If that doesn't work than the MAF cleaning as @2013FSport is recommending

 

I'd reverse the order on that personally especially if the vehicle is subject to multiple short trips of say 5 miles less daily.

More short trips means combustion gasses settle at the TB from the valves being open when the engine off. In addition the PVC system allows fumes to settle in the intake when the engine is off which build up on the MAF. Which is why they have that charcoal screen in the filter lid to keep the carbon monoxide from escaping back into the atmosphere which is why I spray the mesh with MAF cleaner.

At 55k mi I cleaned the throttle body during plug change. At 104k I inspected it during plug replacement and it was still clean. Remember I start it 2x a day and run 28 miles each way. It was it's former life that likely had a bunch short trips that make cleaning the MAF and TB a necessity.

These practices have served me well over the years.

 

I run it hard but I never cleaned the mesh behind the air filter so I will look at that. Use that cleaner for the maf then? I also drive at least 10-15 miles one way sometimes 35+ for work. It has been run hard and gets reved up well so it should run like a champ, but it just has these weird slight hesitations.... may need to clean the maf again too.

 

Interested in knowing if removing the "mesh" filter from beneath the air filter box lid would cause any performance issue or specifically related to lowering vehicle emissions.. I've read some owners have removed the mesh material altogether when installing an aftermarket air intake (Joe Z, F -Sport etc.). Does the IS F also have the mesh filter installed to assist with lowering vehicle emissions?

 

Our use doesn't sound so different. Even at that, it seems to want a MAF cleaning every 6 months or so. I would start there..
Does yours have a tune on it?

IIRC those who ditched it found no gains. That said, I'll continue to hose it down annually. Figure a 1/2 can to really soak it.

 

It likely mostly effects emissions but I wouldn't remove it as you might start throwing codes

 

Understood, thanks AMIRZA786,

 

This is the reason I clean mine once a week, or at least once every two weeks. My work commute is 22 miles round trip. It makes a heck of a difference. I actually just sprayed the MAF this morning. The drive was fun for sure.