Great so we now know, that we are dealing with an FL1 they may just need the tips cleaned, so the spray pattern is good.
Small wire brush.
1a
1
Undo the end a little.
2
3
Do the above a few times slowly so all the grime comes to the top to be cleaned off, before taking the tip and cap off.
4
5
keep a keen eye out for any shims or pins.
6
7
Now the tip is off you need to get the needle out by tapping the edge into your palm of your hand or use a small magnet, the needle should slide out easy, unless it is stuck by a load of carbon.
8
9
Spray and clean the needle with some carb cleaner, let it dry on a lint free cloth or paper towel.
You can now spray out the tip with it's 5 holes for the spray pattern, use carb cleaner with the straw attached.
10
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Lubricate the needle and inside the tip with a small amount of diesel and put the needle back into the tip it should slide in and out freely without sticking.
Then replace the tip with needle back on the injector, always fit new copper washers when refitting the injector back into the car.
You could go the whole hog and clean the whole injector but it is labour intensive, and needs to be done in a clean area, there is a small ball bear which no bigger than a pin head so do not lose that if you do it's game over.
12
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