How to clean injectors?
 

Whats the most effective way to clean injectors?

I'm not sure if there is a better way of cleaning your injectors but you can buy a couple of bottles of injector cleaner from your local kragens, autozone, etc. and put it into your tank the next time you fill up. It should clean your injectors as you drive.

I mean as they are removed from the motor. Just blow air trough them or what?

Well scince you went to all that trouble.
I did it with them removed by getting some carb cleaner and put a little tape aroung the straw that came with the carb cleaner so when installed in the fuel inlet it had a good fit. The you need to open the injector so I had an injector plug from an old harness, hooked the wires to 12 volts and sprayed till the pattern was good once the injector was open.
A little advice though is wear some goggles or something to protect your eyes from getting flying debri or cleaner in them.
Now I use the method mrnickleye talked about here.
http://www.toyota-supra.info/forums/...ead.php?t=4658

there are places that will professionally clean and balance fuel injectors . i think for around $25 per injector

im not sure but i believe 12 volts is to much voltage on the injectors

yeah I would think that 12v would damage something

Correct voltage is around 1.5V to 3V... Using a single AA Battery works great.

Will It hurt the injector if you connect it backwards, I wouldn't think so, I think It just wouldn't open the injector.

I'm not sure if it hurts it... When I did that to test my injectors, they just didn't open when the polarity was reversed. I haven't had any problems with them since I've checked them out, so I don't think it hurts them, but I wouldn't do it if at all possible (just in case it does).