I recently used a high end diesel fuel additive to help clean the injectors and help during the colder Winter months. Shortly afterward, leaks developed at the metalic fuel line connections at the front left and right injectors, as well as one lower connection on the injector pump. Four known leaking connections so far. Tightening or removing, cleaning and reseating the fuel line connections has stopped two of the leak points, but the other two persist no matter how tight I cinch the hex nuts on the injectors. Has anyone had a similar problem when using fuel additives or injector cleaners? And, is there a "fix" for stopping the injector leaks w/ the metal to metal compression fittings? The fuel return lines are holding up fine, but the fuel loss and pooling is a problem.

 

Additives usually do not cause problems.

Look at your injector fuel lines. There should be clamps here and there that organize and clamp the lines together. If these clamps are missing, then more than likely your leaks are caused by hairline cracks in the lines right at the fittings. Been there done that. Those clamps are very important.

 

The line clamps are labelled in this picture.

 

+1 on the anti-vibration clamps. I have had two lines crack from not having them on the truck. They usually crack right above the flare in the tube, under the nut.

 

Thanks for the advice. The diagram is an excellent resource. The four line clamps are all present and secure. As soon as the temperature gets above 30F, I'll take a closer look at the mating surfaces - at the injectors - and metal fuel lines to check for cracks. I'll also try to verify that the leaking fuel is not coming from the fuel return lines. If they need to be replaced, is there a diagram that shows the seal arrangement at each injector location? Kits show washers or seals - 2 types.

 

The return line seals are pretty simple. They are just two o-rings inside the caps, no washers. The only washers are the injector washers that seal the washers to the engine. You don't need to mess with those to replace the return seals.

I bought 5ft of 3/32 fuel line from Napa, and two packs of o-rings from tractor supply. I re-used the caps with no problems.

 

Harbor Freight carries Viton o-rings, I discovered a few months ago: 180 Piece Viton O-Ring Kit