Bought my EF with a sohc ZC over a year ago and rebuilt the engine, etc., I replaced the fuel injector seals (bottoms, cushions, rail o-rings) with Beck/Arnley brand on Rockauto and even the filter baskets (from eBay). Soon after I noticed my #1 injector was leaking fuel, I think around the fuel rail section. I put it off until later, it’s not my daily anyways.

Well I was driving home couple weeks ago and out of nowhere I noticed I didn’t have that much power going into 4th and 5th gears. After I got home I noticed all 4 fuel injectors are leaking fuel externally pretty badly.

I installed a (just one) new fuel injector from Rockauto, and a $15 fuel injector seal set from eBay. The new fuel injector went in #1 with the seals it came with and #2-4 got the new eBay injector seals.

All seals were lubricated with clean engine oil. Fuel rail nuts were torqued to about 10ft.lbs, filter baskets were seated fully. Injectors were seated in the rail first, then installed onto the mani. The “old” o-rings did not have any tears or nicks in them, didn’t see any damage.

All four injectors are leaking at the rail again. However the one with the new injector looks like it’s leaking from the rail - while the other three old injectors appear to be bubbling from the injector body itself. I remember the first set of injector seals I used there were three (?) different sized o-rings to choose from to go in the rail - maybe I need a certain/special size? Or should I suspect something else - too much fuel pressure? Driving me kinda crazy when I know I installed these correctly twice and they still leak.

Also, does anyone know the difference between the bottom seals? There’s some thick ones (used those on mine) and some thinner seals.

 

Is this a stock D16A6 or a swap? It's hard to answer whether you have the right gaskets unless you clarify what you ordered for and what intake setup you have. Only way to know if you have the right fuel pressure is to check it.

 

It’s a SOHC ZC so yeah pretty much the d16a6, ao I bought gaskets for that. Entire car is pretty OE.

Guess I’ll need to buy a fuel pressure tester:\

Are fuel injector O-rings different for ZC engines?

 

I've found injectors leak around the electrical terminals and there's nothing you can do other than replace.

The "new" ones were probably cleaned up rebuilds, and had the leak before and after.

 

i only put in one new injector, and that one looked like it was the o-ring leaking. The other old injectors were leaking at the electrical connector area as you mention. So I think my plan is to buy yet another seal kit for the new injector I just put in, and buy 3 new injectors. Ugh fml $$$.

It just concerns me that all of them started leaking at once like they did... i don’t just want to slap a set of injectors in and they all blow out in a week because of a fuel restriction somewhere causing too much pressure. I’ll take a look at the return line at the tank and see if it’s got a good amount of flow.