Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Fuel injector cleaning

Hello. Just wanted to know if cleaning the fuel injector part of periodic maintenance. My owner’s manual doesn’t mention it at all. It does mention periodic inspection and replacement of the fuel filter.

No, it’s not. It is a favorite money generator for some shops and dealer service departments. Who’s recommending it? Do you have any problems?

Only if you are having an issue like idling uneven or such would you need a shop to flush injectors.
For routine cleaning , I stick a bottle of cleaner in the gas tank once a year and, hence, have never needed to be in the shop.

As already stated, its only function is to prevent you from developing a buildup of money in your wallet. It’s a wallet cleaner.

If you should ever develop an operating problem, it can be used to attempt a fix, but in general your gasoline includes enough detergents to keep your injectors clean.

My indie garage told me that gasolines today have all the needed cleaners in them, and regular additions of cleaner is not necessary. They don’t push the stuff it it’s not needed.

We sold a 1994 Nissan last year that ran perfectly and never had its injectors cleaned.

As said, if you engine does not run smoothly and the spark plugs are OK, a bottle of this stuff is worth trying.

I add a bottle of Chevron Techron or Seafoam to my vehicles once a year or so as preventive maintenance…

Ed B.

Guys, GM vehicles with the CSFI system (the spider) were well known for developing plugged poppets. Sometimes cleaning worked. If not, they got converted to CMFI.

But overall, plugged injectors are fairly uncommon.

I agree with @Docnick. “don’t push the stuff if it’s not needed”

Agree with all of the above. If you have a stubborn problem that seems to be an injector, rather than flushing them the way most shops do, I suggest pulling them out and sending them to a specialty shop. They put them on a test stand and check spray pattern, flow rate, opening voltage and current, and check for dripping. Then they ultrasonically clean them, and run the test again. If one is mechanically or electrically bad, they mark it so you know to replace it. You get your injectors back within a week and you know for sure that they are all clean and working perfectly.

In contrast, if you clean them in place, and the car still does not behave, you still don’t know if the problem might be an injector.

You only hook up the cleaning solution if you are CERTAIN that a SPECIFIC injector is plugged.

You DON’T hook up the cleaning solution if you haven’t definitively diagnosed your problem.

Guessing is not the proper way to diagnose and repair vehicles.

Had a car in our auto repair shop this last week that was running “lean” (either too much air or not enough fuel). After a long series of testing we finally decided to try a set of injectors and this did actually solve the issue.

For those who know what long term fuel trims are:
It started at +39% both at cruise and idle.
We took the injectors out, made a makeshift flow bench, and cleaned them as best as we could.
After running the car again it came down to about 20%.
After installing replacement injectors it came down to 0%.

This is the only the 2nd case in the last 3 or so years that I can think of.

It is very uncommon but it does happen. I agree that putting a 6-10 dollar of injector cleaner in a full tank of gas yearly is a good preventative solution.

Chevron advertises Techron cleaner in their gas. I would say that if you are running Chevron then skip the yearly additive (although it won’t hurt to do both).