FICHT Injector Signal

[ajv00303]

Does anyone know what the Pulse Width and Duty Cycle is for the Fuel Injectors on a E175MFXSOS (2005, 175HP).
I have come-up with set-up to test the injectors but need to know the operating parameters.
Would like to know the info for a engine at idle and maybe 4K-5K RPM.

Thanks,

Tony

[SEAHORSE]

Hooking up an oscilloscope probe to an injector wire would be a quick way to find out while running the motor.

[ajv00303]

@SEAHORSE
I am currently applying ~20ms PW @~ 50% Duty Cycle.
PROBLEM: as soon as I energize the injector after turning on the fuel supply, the nozzle pops off the injector.
I half-assed created a "fixture" to hold the nozzle onto the injector, but the "fuel" (in this case SEAFOAM) doesn't come out of the middle of the nozzle, it sprays out between the nozzle and the injector body.

NOTE: this is all being done on an injector I purchased on EBAY. Any insight is appreciated! Thanks!

It seems like the nozzle is clogged, when I press the spring on the nozzel it "opens " ever so slightly.

[SEAHORSE]

The injector nozzle is kept in place when the unit is bolted to the cylinder head. Get an old cylinder head, and cut off a combustion chamber and use that to secure everything

[ajv00303]

The injector nozzle is kept in place when the unit is bolted to the cylinder head. Get an old cylinder head, and cut off a combustion chamber and use that to secure everything

Understood, but I still think the nozzle is clogged, will try to post a pic later today showing how much it opens and a pic of my "fixture".

[ajv00303]

Below are pics of my set-up, haven't done anymore testing yet.

20230801_163702.jpg20230801_161511 - Copy.jpg20230801_161656.jpg20230801_161832.jpg20230801_162002.jpg
First pic shows injector mounted on a piece of aluminum w/ fuel line for supply and return, fluid id straight Seafoam.
Second pic is bottom of fixture showing nozzle w/ "retainer", third pic is same w/o retainer.
Fourth pic is of nozzle, fifth pic is of nozzle held open, does it look open enough?

[SEAHORSE]

When you think about it, an injector delivers a minute amount of fuel when activated and the pressure buildup is in the hundreds of psi, so the opening of the pintle valve is very slight and open-time is very very short.

On an E-TEC V6 engine at idle, it takes 3.3 hours to consume only 1 gallon of gasoline and it requires about a half-million total injector cycles to do it.