Injectors went bad after oil change?

[Deib]

We bought this used '04 6.0l. It has 75 k miles on it.

As in buying a used truck we started to service it.
it may have had a bad injector when we bought it, but couldn't tell for sure. It was pretty faint.

Now we changed engine oil to Mobil Delvac 15w40. We changed air, oil and fuel filters to Motorcraft from the ford dealer.

It had other brand filters in it before and not sure what oil.

We also filled the fuel tank and used the Ford Fuel additive.

Now we have 3 bad injectors, 1,3, & 7.

I have read where they may stick and is there anyway to unstick them?
Would an oil additive work like Lucas?

Am I way off base?
Maybe we did something when we washed off the engine?

Any help appreciated.

[gary41276]

Ive never tried it but theres a product called hotshot that is suppose to be real good search the forum to find more about it.

[Deib]

Thanks for the response. I have made a lot of progress.

From all the reading, I found a bad battery, that didn't help.

I switched from 15w-40 to 5-40 synthetic. That made the biggest improvement.

However there is still one injector stuck open. It smokes like crazy. I dropped it off at the dealer, we will see what they say.

[bismic]

Glad you are making progress. Once you get oil latching of the injectors (stiction), it can eventually cause permanent issues. The newest flash and synthetic oil are the best things to do for this condition. Do not add Lucas to the oil. Hot Shots Secret is an oil additive that some have had success with, but if the spool valve polishing is bad enough, additives won't help.

fyi:
There is a small spool valve in the top of the injector that controls the flow of high oil pressure fed to the intensifier piston in the fuel injector. That spool valve only moves .017", back and forth, on and off every time the injector fires. Many factors play in to how well that valve works such as, oil temp, oil quality, normal wear, ambient temp, and many others. As this valve ages it polishes itself inside the bore of the spool valve and as the spool valve slams back and forth it can set up the condition like a suction cup, hanging the valve to one side or the other. This uncommanded uncontrollable condition is called stiction. Mostly its a rough run cold condition but in severe cases it can be a no start or pretty harsh misfire condition. Oil that stays inside the valve on a hot engine shutdown and is allowed to cool slowly in the injector can aggravate the condition on restart, so the newest reflash uses inductive heat after shutdown to keep the oil warm, keep its viscosity low, and maximize the oil flowability to purge the oil from them. It has worked fantastic. It is an excellent preventative measure.