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Lucas injector/cylinder cleaner frequency of use

I’ve used the Lucas above very successfully for several sequential tanks full of gas. My mpgs went up dramatically, and the engine seemed to be peppier. But then I was told by a truck driver who also works on racing car engines that it should only be used every 3 or 4 thousand miles or it may eventually burn out parts. Of course, it says on the bottle that it cannot be overused. I last used it 3 tanks full ago, and have seen that my mpg has dropped by 8 -10 mpg. Can anyone say whether I can safely resume using it at every fill up? By the way, I drive a 2002 Toyota Prius, but I also own a 1989 Toyota Camry with only 62 K.

@voicerjim, why are you using Lucas so often?

Did someone tell you that your injectors are dirty/plugged?

I have never heard of anyone using a fuel system cleaner more often than…maybe a couple of times per year…unless he was trying to correct a problem with the way that the engine runs. Did you begin using this product in sequential tanks of gas in order to try to correct a hesitation problem, or rough idle, or…?

In my opinion (disagree if you wish) using a fuel system cleaner very frequently is akin to someone with a compulsive hand-washing problem. You know…once your hands are clean, continuing to cleanse them repeatedly is usually thought of as a sign of neurosis.
;-))

As to this product improving your gas mileage…have you considered that the cost of using this product continuallly will offset (and possibly negate) the claimed saving on gas expenditures? You might want to do some calculations regarding the cost of Lucas Fuel System cleaner vs the cost of a couple of gallons of gas, and see whether you really are saving money.

Truthfully, I am skeptical that any product could improve gas mileage by 8-10 mpg unless there was a serious problem with the fuel system prior to use, but in that case, there is no logical reason why gas mileage would plummet again, right after you stop using the product. Are you sure that you are not succumbing to the Placebo Effect?

In any event, I would be more concerned about doing regular maintenance on the car than I would be about the supposed need to use a fuel system cleaner on an ongoing basis.

I’d stop using it and monitor your mpgs. Once/twice a year should be more than enough.

I say if it makes you feel better, go for it. the people have given you good sense about why you should doubt this cause/effect. It is not the reason. There are too many other variables that are causing your drop or improvement. But if you don’t believe them, feel free to double the dose per gas tank.

It is not snake oil, but just like snake oil, it won’t really hurt your car. Go at it.

I’m surprised that it would affect mpg as much as you report. Are you certain of this? Have you repeated the measurements several times over different driving conditions?

Unless you live in an area where you get contaminated gasoline on occassion, I doubt the need for it at all. My 20 year old fuel injected Corolla w/200K has never even once had a dose of injector cleaner, and still gets the same mileage as it ever has. I think a better use for your money – if your objective is to have pristine injectors – is to replace the fuel filter once a year.

You’re wasting money if you’re adding it more than a few times a year. The only thing I can see that would be harmful though would be if you’re adding it enough that it’s contaminating the oil from blowby in the cylinders. That can cause eventual problems with engine bearings, depending on how much you’re adding and how it’s formulated.

I considered a fuel additive but then I did the math and if I use three or four tanks of (West Coast) Union 76 (with the top tier rating) it is far cheaper than the cost of a gas additive. My mileage has gone up a few miles per tankful. Find the best Top Tier gas in your area. Anyone share this philosophy???

I don’t buy the scenario that using an additive elevated MPG by that much. If that were the case the refiners would be required by Federal law to add it to the gasoline at the refinery. Placebo.

As to Top Tier gasoline, I’ve never noticed any difference at all in MPG between Top Tier or the lesser brands and I monitor fuel mileage religiously; as a means of keeping tabs on any engine performance drop-off more than anything else.

Could the additive be masking some other problem.
What is the actual MPG? (low and high)