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Mileage jumps from 24 to 29!

It has been so effective to add diesel injector cleaner to my 2004 Honda (all of 62,000 miles on it), that it is scaring me. Am I damaging anything? I add about an ounce/gallon every once in a while. Mileage drops back in between.
Any thoughts??

@rosierhill I will assume your Honda doesn’t have a diesel engine? As far as I know, there have been no diesel Accords sold in the US. Unless you have a gray market car, you should stop using that stuff IMMEDIATELY and get the car properly diagnosed. Whoever told you to use that stuff is not to be listened to anymore, as of right now.

I agree. Stop using it. I don’t know what’s in it but I’m sure it’s not designed for gas engine cars like yours. 62k miles is just getting broke in for that car. Stop or you may not see 72k out of it!

I would check to see just what was in this diesel injector cleaner. Just guessing, it would have to be a solvent of some sort. There is some suggestion by some folks that the solvent acetone will make your MPG go up. I would stay away from it as I would be afraid of the effect on rubber parts and such. I would re-check my MPG if I were you. Check tow or three tankfuls before you conclude such a mileage gain. What is in it? Rocketman

This stuff is probably masking some other problem.
If the fuel/air ratio isn’t right this stuff may somehow make the ratio better, but that’s not a good way to live.

I want to give the OP an analogy that should illustrate–on a human level–what everyone is concerned about regarding this automotive issue:

If you take Methamphetamines, you will be able to run faster, have more endurance, go without sleep, and perhaps even experience better sexual performance.
Those “benefits” are during the short term.

Over the long term, you will lose your teeth, you will believe that bugs are crawling out of your pores, your liver will fail, and shortly thereafter, you will die.

Just because something enables better performance of one type or another in the short term, that does not necessarily mean that the substance is beneficial.

Good analogy VDCdriver. I hope you are listening to the comments and taking them to heart rosierhill.

Hey OP! What’s in it? What is the cleaner called? Rocketman

Wow!
To answer the question, it is power service diesel fuel supplement cetane boost with slick diesel ULSD formula…
I ‘get’ the meth analogy for sure!
Yes it is a gas engine. I bought it at 28000 miles from a little old lady who only drove it to church. It was my moms car. I’ve put the additional miles on since October.
Ok. I’m not using it. Darn! I liked 28-29 mpg. I’ve used it in about three fill ups, with time off in between. I keep it serviced regularly at the dealers.

“I bought it at 28000 miles from a little old lady who only drove it to church.”

I hope you realize that her usage (approximately 3,500 miles per year, most likely all of it in local driving conditions) was the absolute worst thing that you can do to a car. That is why car mfrs classify this type of usage as Severe Service, and they specify a much more rigorous maintenance schedule.

Now that you are doing a lot of driving of this car (by my calculations, about 8,500 miles per month), the car is actually benefitting–as long as you maintain it properly. In addition to having used this bizarre, unapproved additive in the gas tank, have you done any other unorthodox types of maintenance?

Take out the Owner’s Manual, and be sure that you are doing everything specified in the maintenance schedule. That includes the timing belt, which has likely never been changed and is now due for changing on the basis of elapsed time.

And, you should add at least one unspecified maintenance item to your list, namely transmission service. If you want to get maximum service from this car, you should have the trans fluid changed every 30k miles, with ONLY genuine Honda trans fluid.

Thank you all for your input.
I have seen the error of my ways.
And I am SO glad that I asked the question.