Having the same problem mazda, two point two engine with azn, regulator and injector of course. Replace regulator and injector, And heists have a stupid filter in between the regulator to the injector replace that as well because it was leaking. Took mixer apart and cleaned everything very, very well. When I started up the large hose, which we call the slow path, From regulator 2 mixer shoots a burst oven L. P when turning ignition on. The injector does nothing. I can start it with some fluid and it will run. I can pull the injector out. It is not doing anything at any time. I see voltage at two wires, but not the third. ECU?

I have a similar problem with a yale forklift, the code 522655-1 comes an goes them it sound like the forklift want to cut off. Did you fix the your ? What did you do to fix ? I would gladly appreciate if any one can help. Thank.

We do not have one of these in our shop right now. The way it functions is. When starting cold, The ECU pulses the injector at a fixed rate. Once the temp sensor reaches a given temp reading the ECU switches to closed loop mode. The pulsing is regulated buy the ECU based in inputs from the cam sensor, the throttle position sensor and the O2 sensor. At idle, the only fuel supplied to the engine is through the trim injector. Once throttled above idle the regulator starts supplying fuel directly to the carb. If you have a fixed voltage to the trim injector all the time the fuel will be delivered in a constant stream and the mixture will be too rich to fire. With the voltage you are seeing at the injector feed wires, I would guess there is a ECU problem or you have a short from a battery wire to the injector supply wire.

Appreciated very much

No. It should be going to 0 volts then back up. I will see if we have a unit I can check the voltage on.

I have 10.2 volts with the key off or on and when you start cranking it goes to 11.4 and goes down to 8.6 and back up to 11.4 and back down again, is this what you are referring to? and when I checked for hz I get nothing. I have a brand new injector but do not want to plug it in and burn it up.

Unfortunately no access code, we inherited this unit from a facility they closed in Wisconsin and it came with this problem.

The most common cause for surging is a misadjusted accelerator pedal or the pedal position sensor is defective. Do you have access to the service password for the display?

Check to see if there is any voltage at the connector. If there is you have a bad injector. If not there is a problem with the engine ECU. The voltage will not be constant. You need ammeter that can measure Hertz. It is a pulsed signal from the ECU.

It does not pulsate at all.

Remove the trim injector, leave it connected. Turn on the ignition switch. You should feel it pulsing. If it is not pulsing replace it.

Just replaced the Asian regulator and cleaned the injector now it will not start, has fuel, fire and air. Update, it has to be started on carb cleaner and after starting it it surges at idle until you get to a higher rpm, what would cause it to surge? No codes

522655-1 Closed Loop Feedback (LPG) Short Term Fuel Trim High.
This means you have an intermittent lean run. You might try draining the solids out of the vaporizer. If this truck has the trim injector take it out and clean it with carb cleaner.