I open Air housing hose at 125K on my 94 LS400, at that time, I replaced spark plugs. It was very clean no deposit build up inside the Air housing next to the throttle. I put 2 bottles of Chevron Fuel Injection cleaner on my fuel tank at 125K, then at 127K, I have chance to take out the Air Hose again. OMG there is tan color like corrosion build up right underneath the throttle. Well, the only think I can think of is the Fuel Injector Cleanup might caused it, because why for 125K I did not have but at 127K. I can not think of any thing else because that was the only thing that I add to my fuel within that 2K miles interval.

For my car I think I would never use any additivity again. Except when there is problem then I might.

Anyone used Chevron Fuel Injection Cleaner saw this symptoms????

 

Maybe it's all the bad stuff leaving the system?

 

Has the fuel filter been replaced? If not, the chevron fi cleaner may have blown that stuff out of the filter and sent it down the line. I have used this stuff for years with no bad effects, just don't overdo it (don't use it every tank), spread it out about every oil change or so, overuse can melt some glue that holds the fuel injectors together. And always use good trusted gas. I would clean all the visible stuff and check it again in a month or so, it should come off over time.

 

GA400 and 2jzgte,

Thank you for your responses, It's really make sense now. No, I have never replace the fuel filter. I think I just don't use any additivity for now. I might use it when there is problem.

Thanks again.

 

Yeah,

You should check the fuel filter. I have been having a good gas mileage by using chevron Fuel injector cleaner and please stick to the same brand (I mean, please stick with MOBIL if you have been using MOBIL) and grade when you buy gasoline !!! Those gasoline companies out there have different mixtures in their product to produce high octane.

Trust me, My Dad used to work at an oil refinery, That's why I know.

I hade been using grade 91 of Chevron and Duralube oil engine treatment. No complaint so far !!

Good luck

 

LS400Dom,

Thank you for your advices.

 

I use some of the worst gas on this earth, Pemex, and I have to have my fuel filter changed every 9 months or so, even on 93 premium. If you ever go to Mexico and it smells like sulphur, that is the rotten Pemex gas.

I have used the bottled Techron for some time now. I can tell you for a fact that the fuel filter is full of .... at the time of replacement. I also use another product called Restore and recently saw the sludge coming out of the engine at my proximate oil change.

Did you notice when you began using Techron that the car would not often turn over unless you gave the pedal some juice?

You can use it every tank, just do not throw in the whole bottle of Techron, maybe 1/4 each time. In fact Chevron gas has Techron in it.

 

The Toyota, Honda, and Acura dealers where I live all "use" BG 44K as the fuel system cleaner. Some people say it is just a super concentrated Chevron Techron. On one of the "oil" www's, everyone there only says great things about it. Ask around. You may want to try it.

 

There are a lot of good things for our beloved Lexuses these days. I would not be surprised if it is repackaged Techron. Restore also makes an injection cleaner, and also consider trying AutoRx.