How do I turn off fuel pump and close return line for an injector flush?

[ti286]

A tech at work will help me to flush an injector I identified as clogged. He needs to know how to disable the fuel pump and close the return line so we can isolate that fuel rail for a flush.

He plans to introduce the cleaner to the rail, but only activate the #7 injector by connecting it to the battery. We'll need to know what voltage the injectors operate at (7, 9, or 12 watts).

[elwesso]

At idle, just pull the fuel pump fuse, in the passenger compartment... its like the 4th one down on the right.....

I woudl recommend you do the fuel cleaner with the engine running (fuel rail flush)... you can fry the injectors with direct voltage for morethan a few milliseconds.....!!

[Q45tech]

Confused voltage vs. watts? 13.2 volts x 1.0 ampere = 13.2 watts/13.2 ohms= 1.0 ampere.The injectors all receive batterry voltage and are switched on by grounding thru ecu..............thus they are called saturated type.

You will hydrolock the engine [bend a rod] if you don't do a running flush!

We loop the 2 rubber lines going to the rail and thus leave the pump circulating directly back to tank............then block off the output of rail and pressurize the input of rail with a tank of BG Induction cleaner to run the engine at idle.........clean all 8 injectors while the engine idles 15 minutes.

[Q451990]

Tech,

Would ECU let the car run if you pulled the fuel pump fuse during all of this?

Heath

[911/Q45]

I'll jump in before Dennis and say yes. If you pull your fuel pump fuse now the engine will continue to run until the fuel in the lines is depleted. Should work the same with the line looped, the ECU doesn't know whether or not the pump is running.

[elwesso]

I can also say that, because on my fuel cell setup, when the external pump was engaged, the in tank pump's ground was cut. So in essence it was doing the same thinga s pulling the fuse....

[maxnix]

Should work the same with the line looped, the ECU doesn't know whether or not the pump is running.

I believe you are correct on ODB I.