Shortly after I bought my 01 UL, I was persuaded by the auto shop to flush the fuel system. Although it's not terribly noisy, it's never been as quiet as before!! I'm not sure what went wrong, and I don't think the flush can be "undo" anyway. Anyone had experience with this or have any suggestion?

 

maybe you just have to ride it out. or maybe gas treatment.

 

What is a fuel flush? Bleed out the fuel system and then repressurize? I guess the promise of doing this is to "improve" fuel efficiency?

Ugh... sorry to hear.

 

Maybe they were thinking about the filters that get clogged when the tank is overfilled. I'v heard something about this problem, and was quoted something like $2500 for repairs. Was cautioned by several people to not overfill the tank.

 

The flush is basically cleaning of the fuel injection system according to the service guy. I wouldn't be surprised if they bleeded out the fuel system and repressurized it. The engine has become noiser since then, which I remember vaguely that it was indeed very quiet prior to that.

 

For what it's worth, neither Toyota Motor Sales (Toyota USA) nor Toyota Motor Corp (Toyota Japan) approve of or recommend dealers do these "supplemental services" as they are known in the industry, on the engine, transmission, fuel system, steering system, etc. They state clearly that they are NOT needed to properly maintain Toyota products, and that some of the chemicals commonly used in these flushes may not be compatible with Toyota fluids and may cause damage to the vehicle.

This type of service is a big money-maker for maintenance and repair shops though because they use about $5 worth of product and charge about $200 for the job.

Also, re: your comment above, the fuel system de-pressurizes over a period of time (duration varies depending upon the vehicle, but it's generally not longer than a couple hours or so) after you cut off the engine (and hence the fuel pump). It repressurizes the moment you switch on the ignition and the pump starts. Some shady service guy may make it sound like this "repressurization" is a special process that you should pay them for. LOL

Re: the increased noise you mention, what does it sound like? Is it a ticking sound, or what?

 

Fyuen - Sorry to hear. Where in WA are you?

Have you take it back to the shop who did the flush?

 

Let me apologize for my poor word choice. By saying engine "noise" what I really mean is the engine sound being too noticeable. That's no strange noise such as ticking. However, I can now easily hear every bit of engine sound whenver I step on the gas even with light push. I still remember in the past the engine was so quiet that its sound became noticeable only if I really stepped on the gas hard to get to a higher RPM range. But again for a non-Lexus owner, it may appear normal to them since they have no clue how quiet a typical LS430 engine SHOULD be. Hope that helps to clarify my question.

 

BTW, I didn't bother to bring the car back to the shop because that will definitely seem normal to them (of course, if compare with other average car on the road!)

 

It's still not exactly clear to me how the sound has changed -- if it's the exhaust note or the intake note, or mechanical clatter (about the only noises an engine makes that I can think of off hand) but just for the heck of it I'd check to be sure they put the engine air filter, housing, etc. back in place properly.

 

turbo's probably right - if they didn't put the air cleaner assembly back on properly (or left out the air filter!) you will hear intake noise much more than you did before. Let this be a lesson to you - never fall for the BS 'Flush' procedures. Your tranny doesn't need to be flushed and neither does your fuel system. Brake system? Yes.