Cleaning fuel injectors is our main business. Some of the cleaning we do is of OEM cores that are then sold to customers as replacements. People buy them for all sorts of reasons. Upgraded flow and spray patters over stock injectors like with Jeep 4.0. Needing a spare set for a boat like a yamaha outboard because they foul constantly due the the ethanol content in the fuel in their area. Some just don’t want to wait because they don’t want to wait to send their set in for cleaning and testing.

No matter the reason, cleaning does the same thing to an injector. It strips any lubrication inside of an injector which can lead to an injector sticking shut or open from not having gasoline run through it. When testing a cleaned injector, we use n-Heptane. This has no lubricating properties, but is the same specific gravity of gasoline while being safer to atomize indoors. After testing, we do try to lubricate with a light oil. However, an injector is a sealed unit and cannot be lubricated completely each time. We rely on gravity to pull the lubrication through when applying. This can lead to a part of the injector being “bare” and getting “stuck”. The small amount of amperage delivered by the signal to fire the injector can not be enough to break the injector free to start operating as it should.

Why did this happen to my cleaned set

Time is the biggest reason. For some, they had the injectors cleaned and returned to them, but let them sit for a while ( a month or so) before re-installing them. Another reason that usually happens to a new injector that ran great right off the bat, but is now showing issues a short while later is caused by debris. Older systems can be disrupted and the debris loosened has found its way to or past the injector filter. In this case, re-cleaning the injector is required.

Still time related, but for purchased injectors from us. We try our best to keep needed stock on the shelf for quick turnover part numbers. However, our crystal ball is still in the shop broken! Our goal is to only have enough fresh and ready to ship for a 2 day supply. Sometimes, sales slump for a few days or a week and a set might have sat for 2 weeks and it was pulled from the shelf to fill an order. Maybe that customer waited another week or 2, and now its stuck.

None of this is a huge deal, but we recognize it is a pain in the rear.

What can be done?

A simple solution that works about 95% of the time is to simply tap the cleaned injector’s side with a wrench or something to “jolt” the injector enough to free it up. It is best to do this while the vehicle is running. Even if it is running rough, attempt the tapping while running.

If this does not work, please contact us and we will be happy to help.