Soaking in gasoline works and also spray some carb cleaner in them to clean that fine screen which you can see when looking down into the top of your injector, also I used a spare pig tail and a 9volt battery and what you do is spray some cleaner in there until your injector is full and then hook it to the battery and let it run through and I would get some new o rings while your at it they sell the O ring kit at any auto parts store and its like 3bucks and you'll need two kits, any questions just email me
scrapla@hotmail.com