Dealer repeatedly recommending "Fuel injection Air mass Service" for my 2010 Prius

No. Unless the car is throwing a code, there's no reason to perform cleaning of the mass airflow sensor or the fuel injectors. I can't imagine what else it could be. Moreover, cleaning both of these wouldn't take a mechanic more than an hour and $10 worth of cleaner, so the $350 is outrageous too. It sounds like they are pushing this service for commission checks. Probably time to find a new place to have your car serviced.

 

You can do the injector part of that service by treating your engine to a recommended dose of Techron twice a year or so.......at about a tenth of the price the dealer wants.

The intake probably does need to be cleaned at some point; a half hour of labor and a dollar's worth of cleaner. Less than $100.

 

Forward the letter to Toyota corporate and ask them what they have to say. And Sam's right, putting a quality treatment in the fuel tank does a great job of keeping the system clean. As someone who worked in shops and performed and sold services like these, I can tell you that they are one of the easiest and most profitable services that they can offer. They are also one of the most over sold and unnecessary.

 

Relay the whole story, include the red text on invoice. Pure pressure tactics. Too, if possible: any other nearby dealerships you could try?

You might try talking directly to the Service Manager, but might well be a waste of breath.

 

My advice is to go in for what you want as far as service and do only that. If anything else is recommended, just ask for a written estimate to take with you. An easy out is to just say something like

"I only budgeted the time and money for what I came in for today. Thank you for letting me know about the other recommended services. Will you give me written estimate to take with me so I can look them over and set aside the time and money to cover what I decide to get done? Also, would you mind ranking them in order of importance for me so I can make a more informed decision on what order to do them?".

Then you can take the estimates to someone with a better knowledge base to make your decision. Obviously, if you feel comfortable about it, make your own decision. There are some circumstances where it does make sense to do extra things. An example would be going in to get a radiator hose replaced and the facility saying that it would be good to replace the coolant, or having to replace the water pump and them saying to replace the belt. In both cases there isn't much point in putting the old coolant or the old belt back on. In the case of the Prius, the isn't a water pump belt, those are just examples. I'm sure if you bring the estimate home and post on here plenty of people will give advice and tell you if the price is in line with what others have paid as well.

 

It's not recommended, go find a new dealership or just do it yourself.

 

Both the dealers by me, ask them to do preventive maintenance, like a fluid change in the transaxle, and both come right out and say no, it's not due until 100K. That's why I downloaded all the maintenance videos because I don't want to looking at $1000 or more in required services between 100K-110K. Ditto on using a good fuel system cleaner like BG 44K or Techron once or twice a year.

 

The transaxle fluid change is never "due". Hasn't stopped me, just saying.

 

I just bought the fluid to do it as well. I should be at 95000 at my next oil change, and I'm going to do it and clean the intake and PCV as well. May yank a plug and if they look bad do them too.

 

My dealer has tried that for the last three services in a row, I give mine a bottle of Techron twice a year, I average over 52 mpg almost without fail even at 145,000 miles. Just another attempt to get in your wallet. I get the letters of neglect too, I think it's kinda sad that people will fall for it. I always ask the writer if I'm getting over 50 mpg and car's running great, why on earth would I let you screw with it? They never have an answer other that it's what we recommend, I ask you or Toyota? Last time I was told Toyota doesn't always know whats best.

 

It doesn't hurt to clean the Mass Air Flow sensor, very infrequently, say once in the vehicle's life? I think that's what they're on about. There's a special cleaner for it, and it's quite delicate.

It's just troubling that they're so pushy, and maybe they should explain what they're offering better.

I don't think Techron gas treatment would be doing anything for the MAF sensor BTW.

 

I think your right Mendel. Unless there have been some radical changes I'm unaware of, which is possible, the Mass air flow sensor measures air coming into the intake, so a fuel treatment would have no effect at all on it. I can see cleaning, but I'm not sure with what. I'd have to check, but you would think making sure it was free of debris would do the job. Maybe something similar to what's used on AC coils or just ether.

 

Would this "Fuel injection air mass Service" means cleaning the whole intake system from throttle body all the way to combustion chamber, by using something like the BG Air Induction Cleaning product?

I was worked at Honda stealership as a service tech long long time ago and advisors sold this exact BG Fuel/Induction cleaning service. I used this on my AE86 Corolla, and it actually cleaned up the intake manifold very very good. Can this help solve problem with the intake oil puddle, dirty PCV valve blowby, and clogged EGR pipes on our Prius?

 

And I think you are right about that.

 

But the point IS that the "whole intake system" does NOT NEED TO BE CLEANED on most vehicles, even ones with really high mileage.
A little fuel residue inside the intake manifold, a little carbon in the combustion chamber and a bit of sludge clinging to the inside of the valve covers or in the oil pan DO NOT INDICATE A PROBLEM THAT NEEDS TO BE FIXED.

And the sudden proliferation of users on here hawking BG products is a bit bothersome.

 

And some will continue to promote this "wisdom" until their headgasket breaks or their engine burns 1q oil per 500 miles or it develops a misfire...

The only way to know for sure it needs it is to disassemble and look.

Based on my experience you can't go wrong with a cleaner air intake system as long as you follow the directions and not hydrolock your motor.

With that being said there are more effective ways to clean your intake manifold and EGR system than running cleaners through the fuel system.

Pixel XL ?

 

I think the cleaning is something that should be done, I just think that the dealer charging an unreasonable price is wrong. You will get most of the same benefits by putting a quality treatment in the fuel tank anyway, in my opinion. Some people on here like BG, others techron, I like Lucas. I don't think it makes much difference as long as you do it. Keeping a clean air filter is equally as important. You need good air flow as well.

 

As far as the MAF sensor goes I've never had to clean one in any of my Volvo's, 125K, 370K and my present 97 960 with 122K on the odometer. If you're using a quality factory quality air filter or better and change it at the recommended intervals there is no reason you should need to clean the MAF. I could see a problem if you were using a oil coated unit like a K&N and the oil ended up coating the fine wires in the sensor.

 

This isn't a Volvo. Toyota has a charcoal element on top of the air filter to catch gasoline fumes. The Atkinson engine regurgitates it's air/fuel mix every revolution. Intake valves are held open to get the 8:1 compression and 13:1 expansion.

So I can see it's a possibility to foul the MAF if there's bad fuel or torn air filter.

Pixel XL ?