Cleaning Injectors

I had some extra 450cc injectors so I was trying to figure out a way to clean them outside of the car. Resort to other sources for instructions I may have missed.

I cannot stress enough how DANGEROUS working with fuel is. Make sure you are in a well ventilated area. Please do not smoke, make sparks, use space heaters, bare light bulbs, so on.... I kept a Fire Extinguisher close by just in case. Also, check for leaks when finished installing. Cars have been known to be engulfed in flames within seconds. I also suggest wearing gloves while working with fuel. Do at your own Risk!!

Click here to see how bad a fuel fire can be

I had relieved the fuel system already (use other instructions) to do the fuel filter.

Take a precision screwdriver and remove the clip as shown above from each injector.

Remove the fuel line from the regulator. For the big line I inserted a bolt to hold gas inside. The vacuum line is indicated by the smaller arrow.
I removed the harness from the TPS (precision screwdriver clip thingy) and the hose from the PCV valve. You need to remove them to get the rail off.
Remove the 3 bolts holding the rail down with a 12mm socket, This pic shows the cables removed and pulled back out of the way (held down by 2 bolts).
Remove the three bolts hold the wiring to the intake (10 mm). This enables more flexibility.

Now on to the cleaning part. I determined by using an amp meter (on harness) that the injectors get between 1 and 2 volts per injector while engine was turning over.

An AA Battery has 1.5 volts. Here I show a battery with two leads (ripped from flashlight) taped securely to contact points.

On the side of the injector there is a POS + sign. I clipped the red wire to that. Black clip to the other terminal.

When connected (POS+ and NEG - written on battery) it opens the injector allowing fuel to pass through. I blow air on the rail and unhooked nothing came out, but connected it did.

I took the fuel line off of the side of the fuel rail and taped up the regulator holes.
I used the bulb from one of the cheap siphon pumps they sell at most auto stores and jammed it into the end of the rail. It sealed well so I filled the rail and half the bulb with Carb Cleaner.
Luckily the end of the of the bulb sealed around the end of the air gun. I added some pressure inward to make a good seal and avoid spraying cleaner everywhere.

I placed the battery hanging above away from the rail (to avoid sparks). I clipped the wires to the injectors first (red to POs +, Black to NEG-) and then the battery.

Using the gun set at 25 PSI, I shot air through the rail to push the cleaner through. The rag is to block spraying cleaner.

Here are two pictures showing the cleaner passing through the injector (the best pics I could get).

I did each injector twice going up the rail and then back down.

The pic shows another way to blow air through using a 3/8" fuel line fitted directly on the injector itself. Fits snug but holds very little cleaner. The bulb could work here also. I used this method to blow air through a third time.

I cleaned the rail with the injectors out and let it dry. I stuck a rag wrapped around a nut driver in the holes to remove buildup.

I added oil to the O-Ring before reattaching the fuel line.

Note how terrible my hands look (dried out). Why You should wear gloves. Do as I say not as I do.... : )

Add oil to the O-Rings on each injector as well. Also, you should replace these before reinstalling.

I found it easier to place the harnesses on each injector then set it in (less room to work when in).


The top arrow shows the seal on the head. I had a vacuum line in there to suck out crud.

The bottom arrow shows the round washer the rail rests on. I used RTV on these to keep them in place for the reinstall. (They kept falling off).

When rail is in add bolts and hook all wiring, lines and hoses back up as they were. That's it!