Ford Racing M-9593-LU47 - Ford Racing 47 LB/HR Fuel Injector Set (2024)

FAQs

What should a good fuel injector read? ›

Use a multimeter to take a resistance reading. Check your vehicle's service manual or online to learn the correct value (most fuel injectors should read between 10 and 18 ohms).

If you have a turbocharged 1.8L engine making 220 horsepower - for example - a small "bump" in fuel and air flow could easily yield a 10-20% horsepower increase, or about 20-40hp. But if you have a 300 horsepower 3.0L engine, a 10-20% increase would be 30-60hp. Of course, every situation is different.

For most race engines, Flynn says that the ideal maximum you should see on a duty cycle display for the fuel injectors is 70 percent. Duty cycles higher than 85 to 90 percent risk running into inconsistent fuel delivery issues.

Bigger injectors inject more fuel than stock injectors do. So when bigger injectors have the same duty cycle and timing as stock injectors, the engine's going to get too much fuel. When that happens, you won't notice an obvious gain in the engine's power. Instead, the engine will run too rich.

Bigger is not always better

This can lead to fouled spark plugs and damage to the engine.

Fault codes associated with a clogged fuel injector are the P0300 thru P0308 series, which indicates the engine controller is seeing an engine misfire.

Cleaning fuel injectors at home requires the use of a fuel injector cleaner kit and a basic set of tools like a wrench. The injectors must be removed from the fuel rail system, cleaned using a prescribed injector cleaner solution, and then reassembled back into the engine.

In the end, do not upgrade to larger injectors in an attempt to get better fuel mileage, as new stock sized injectors will do the job if your current injectors are worn out. But at the same time, if you are looking for more power, do not be afraid to go to a larger injector because of losing fuel economy.

Essentially, this is all the balance rate is measuring. When viewing the rates, a cylinder with (+) means that its injector is using more fuel than the average fuel rate and a (-) translates to less fuel. GM states that balance rates should be no more than plus or minus 4 (+4/-4) in park at operating temperature.

Fuel Injector Calibration

When one or multiple injectors do not deliver as much fuel as the others all cylinders will not have the optimum stoichiometric mixture. The engines computer adjusts the fuel mixture based on all of the cylinders and if some are running rich then others are running lean.

What is a normal injector reading? ›

As injectors wear, their efficiency decreases, which is evident from the total injection volume at warm idle. New or healthy injectors will typically display readings between 5.5 and 6.5 mm³ per stroke. When these figures rise beyond 9.5 mm³, consider inspecting the injectors for potential replacement.

A typical pulse width is 2 to 4 milliseconds at idle and as high as 15 to 18 milliseconds at wide-open throttle.

generally if the correction values are between +2/-2 (for some cars +1.5/-1.5) you shouldn't worry about them .. If the value is minus it means that injector is overfueling ...and vice versa ..

Even if the value of Injection Feedback Val for a cylinder is less than -3.0 mm³/st (-3.0 mm³/st is the lowest normal value), as long as the value of Injection Feedback Val for each of the other cylinders is 3.0 mm³/st or less, the fuel injectors are not malfunctioning.