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FUEL : Bench Cleaning Fuel Injectors (on the cheap)

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    FUEL : Bench Cleaning Fuel Injectors (on the cheap)

    I recently had the need to clean my fuel injectors without putting an additive in the fuel tank so I did some research and found out how to clean the injectors outside the car. This can be done for cheap without any expensive tools or equipment.

    A clogged injector will cause the car to run and idle poorly, as well as; you will get worse fuel economy and the chance of early detonation will increase.

    Tool List:
    10mm wrench or socket
    17mm wrench or socket
    Small flat head screwdriver (to remove injector clips)
    Voltage Meter (that can read ohm's)
    9v battery
    Wire leads with small clamps
    Varying diameter of tubing
    Cleaning solution / dissolvent (ie.. carb cleaner, throttle body cleaner, brake cleaner, etc..)
    Syringe (optional)

    Step 1: Disconnect battery, you will be working with fuel in the engine compartment so minimizing the chance of a spark is a good idea.

    Step 2: Remove Injector wiring harness from injectors.

    Step 3: Using a voltage meter test each injector to make sure they all have the same ohm readings ( this will tell you if an injector is just clogged or completely dead).

    Step 4: Once you have verified that all the injectors have the same ohm readings, you will need to take them out to clean. Do this by first disconnecting the fuel line (its a good idea to have a small cup or jar to catch the fuel that will drain out of it), then disconnect the fuel return line and the fuel pressure regulator vacuum line. Then its 3 nuts on the backside of the fuel rail, then slide all the injectors out with the rail (I had to remove 2 injectors from the rail to actually get the rail out as it hit the another component causing it to not come out (on a jdm H22a)). *When removing the Fuel rail and injectors make sure you do not knock out /loose any of the orings, washers, or fittings the injectors sit in.*

    Step 5: Now that you have the Fuel Injectors and Fuel Rail removed, go ahead and remove the injectors from the Fuel Rail (keep track of the order of injectors so that you can put them back in the same order they came out.

    Step 6: Take an injector and remove the small mesh "filter" out of the end as well as you will need to remove the o-ring at the top of the injector. This is a god time to inspect the O-rings and to see if any need to be replaced (it is a good idea to go ahead and replace the O-rings as it will minimize the chance of a leak in the future).

    Step 7: With the O-ring and filter screen removed take a piece of tube and slide over the end, then from that tube you will need to step it down to the appropriate size tube, depending on how you plan to "spray" your cleaning solution. This can vary from a spray can to a syringe with a tube, I used a spray can with the red spray tube. Whichever method you use, you will want to make sure that it is sealed and held together properly as it will come under pressure.

    Step 8: Now with your spray method attached you will need to take two small wire leads / clamps and attach one to each of the prongs on the injector where it plugs in. Then take the other end of one lead and attach it to a 9V battery. DO NOT ATTACH THE OTHER LEAD TO THE OTHER SIDE OF THE BATTERY, you will be tapping that lead to momentarily open the injector if you hold it open it can overheat and fry the solenoid in the injector.

    Step 9: Now that you electrical is connected and your spray is connected its time to clean. Slowly depress on you spray can (or syringe) while simultaneously tapping the second wire lead to the other side of the battery, this will cause the injector to pulse open (like it would in the car). As you tap the wire lead, put more pressure on the spray until you hear the injector spray hard, and you see the spray pattern fan out. Once you get to that point let it cycle at that pressure for a couple of "hits" and then let off the spray.

    Step 10: Disconnect the wire leads and your spray and repeat steps 6-9 for the remaining injectors until all are cleaned.

    Step 11: Using new o-rings, (or old if they are not too worn out but not the best idea) put the injector/rail assembly back together. It is a good idea to clean the small mesh screen filters before you put them back in the injectors, a quick spray of cleaner should do the trick (DO NOT SOAK THE FILTERS OR INJECTORS IN ANY CLEANING SOLUTION AS IT CAN CAUSE THE PLASTIC TO BECOME BRITTLE).

    Step 12: Install the injector/ rail assembly back into the car and attach all the hoses and lines. Clean up any spilled gas and wait for any fumes to dissipate, then reconnect your battery.

    Step 13: Turn the key to the On position several times to prime the Fuel rail, and once you verify there are no leaks start your car. While the car is running double check for any leaks. If you are doing this cause of a dead cylinder now is the time to make sure that it is fixed, you can check this by pulling off spark plug wires one at a time and listening for the car to bog.

    Since you just spent time cleaning your injectors it is a good idea to make sure they stay clean by changing out your fuel filter.

    (I will update this D.I.Y. with pics once I get them uploaded to my computer)

    If at first you don't suceed, then skydiving is not for you.

    I try not to down talk anyone, when I read my old questions I realize I was an idiot too.

    Very nice write up. Thank you
    FSAE (F Series Accord Enthusiasts) ..."A dying breed thats taking it to the next level" Lucky #13
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