Fuel system flush?

I recently bought a 2003 Toyota Tacoma with the 2.4 L engine and 160K miles. It seems to run fine. I took it into my Mechanics Files mechanic to have a couple of things done and he recommended doing a fuel system flush for like $300. My daughter has a 2008 Yaris w/ 100K. She took it to her mechanic recently (on the other coast) and he recommended a fuel system flush (for about $150!!–and she’s on the West Coast, I’m in VA). She thinks her gas mileage is a little off (only getting 38 mpg !! ??), but otherwise the car is running fine. If these vehicles are running well, is there any reason to get this flush done? The idea that it may increase gas mileage if otherwise running well seems doubtful to me. What does the Car Talk world think?

It seems to run fine

If it ain’t broke…

+1 to @Shadowfax. If you really think you need this, go to Walmart or a McPArts store and get a can of Seafoam or similar and put it in your gas tank. You can send the money you saved to us :wink:

Seafoam? Does that really work? Oh, and I just called the mechanic to re-check the price they gave me. Actually it was $253.48, and that included cleaning the air intake system (122.40) and the fuel injection system (131.08). But yeah, I’m in the “If it ain’t broke” school. Incidentally, these guys shot themselves in the foot when they quoted me $65 to change the differential oil. Did it myself–about $10 for 2 quarts of 80W90.

Stay away from these types of places. There is a time when a fuel system may need to be flushed but these type of places are really just flushing your wallet…of cash.

Yes, seafoam works. In fact it works well enough that you need to be careful how you use it. If you put it in the oil you should only drive a short distance before you change the oil to get it out of there, etc.

I really like cleaning the intake system, as though it’s a dryer vent that you have to scrub out from time to time. What a joke.

Stay away from these types of places.

It’s getting more and more difficult these days.

The blanket statement that X, Y, or Z is never needed is incorrect. There are many times when an induction or fuel system cleaning is necessary.

Many end up in this condition, or worse, at far fewer miles than this one did.

But that TFSI has direct injection, right?

Intake cleaning is worthwhile if there’s a problem to be solved.

There’s a lot of times that problems exist and the owner of the car is blissfully unaware of it. I’ve test ridden with people over some issue and who have never noticed tire vibrations, pulls to one side or the other, pinging due to whatever reason, transmission shift flares, mushy shocks or struts, noisy brakes, tire tread wear irregularity noises, and in some cases have never paid attention to that rapping rod bearing…

So the fact the car owner notices nothing does not mean a problem doesn’t exist. Of course, even mentioning any of that stuff they’re oblivious to can sometimes mean the “uh oh, they’re trying to rip me off” thing comes into play.

Look how many people have posted on this forum after an oil change fiasco leading to a wiped engine and the vast majority always claim the oil light never came on. It did; they just weren’t paying attention. If they don’t notice a red oil pressure lamp then odds are they’re not going to dwell much on anything else that crops up.

2003 Tacoma? 160K? Me, I wouldn’t allow anyone to mess with the fuel or air intake system unless there is a drivability symptom. If they told me the air intake system needed cleaning, me, I’d take the works apart and see for myself. On my Corolla at least removing the throttle body is a fairly simple job.

It is true what OK says, that area can get pretty gunked up over time and miles. On the Corolla the source of the gunking is mostly from the PCV system. But the EGR contributes also. Once the throttle body is off though, cleaning all the gunk out isn’t that difficult.

On some vehicles removing the throttle body is a big job, might involve the cooling system and the fuel injection system. On those, it makes more sense to at least consider having it proactively cleaned out at a shop.

Fuel system flush is generally about as useful as tire air change.

Cleaning the throttle body and IAC valve should be part of the regular maintenance but 15 minutes of labor and $5 for cleaner should take care of it.

All depending, sometimes aerosol cleaners won’t clear up the problem.
A few years ago I basically had to chisel my way through the EGR passages on my son’s Camry.

A dealer I used to do side work for sent me an old Jeep CJ one time with a bad transmission.
I discovered the trans was fine. The reason it wouldn’t shift was because the modulator vacuum nipple on the intake manifold was plugged solid with hardened carbon. Aerosol cleaner would not soften it and a pin punch would not break it loose. I finally had to use a drill and bore my way through it with a 5/16" bit.
The modulator on the trans was good; it just couldn’t get any engine vacuum. The dealer of course was happy over that one.

Unless there’s an operating problem, and in your case there apparently isn’t, than the flush simply prevents unnecessary deposits from building up in your savings accounts… and transfers them to the shop’s bank account.

You should also be aware that modern gasolines have sufficient detergents to keep your fuel system pristine as long as you don’t do anything dumb, like try using heating fuel oil instead of gasoline to save money. Don’t laugh, you’d be surprised at some of the questions that people ask.

“You should also be aware that modern gasolines have sufficient detergents to keep your fuel system pristine”

Then how do you explain the occasional fuel injectors that are partially plugged and really do need a flush?

"You should also be aware that modern gasolines have sufficient detergents to keep your fuel system pristine"

Then how do you explain the occasional fuel injectors that are partially plugged and really do need a flush?

I’m not convinced on this one either. Maybe the high-tier gas is (which I don’t have anyone even close to me). Every fuel filter I’ve ever pulled off a vehicle was FILTHY.

It seems like you would feel sticking in the throttle if that was gunked up. I got a sticking throttle on a '95 Saturn I used to have. That was easy to access and I cleaned it out by hand w/ a can of spray cleaner.

Most new cars have electronic throttles, so the driver won’t be able to tell.

So how is a customer to differentiate between a service that is actually needed and a BS recommendation for a service when the service in question is one that is famous for being recommended unnecessarily to pad profits?