Injectors still leaking...

[Rennen]

Ok, I need a little help on this one.

A friend of mine has a 1990 240SX with KA24E. The first injector towards the front of the car(#1?) was leaking real bad. I had recently replaced one of my own injectors with one from an extra fuel rail I bought from someone parting out their car. I still had the rail sitting around so I replaced his with a good injector from the rail. The rail and injectors were from an 89 SOHC.

Anyway, the injector(we replaced) was still leaking a week later, so I pulled it out to see what was wrong. The O-ring had been shredded even though it looked fine when we installed it. I pulled the rail off to see what was making it tear, and found a small scratch on the inside of the rail where the O-ring would seat. Concerned that this is what was tearing the O-rings, I replaced the entire rail, but used the remaining 3 injectors and replacing the #1 injector with torn O-ring. We torqued it down and reconnected all the vacuum hoses, but now the Idle was horrible. The engine would shake back and forth a lot! I checked the vacuum hoses to make sure I hooked them up correctly and everything appeared to be fine. Also, it didn't sound like the engine was missing, so I think all of the injectors worked. So I sprayed a bunch of carb cleaner into the throttle body and MAF to clean things out and the shaking calmed down a bit, but was still worse than before. Also, there was liquid spraying out of the exhaust, it was odorless and had the consistency of water. At this point it was getting dark so we quit, and as he was closing the hood, I noticed that the #1 injector was still leaking!


Sorry about the long story, but anyone have any clues as to what could be wrong?

-Matt

[driftmaster04]

try running some injector cleaner like valvoline fuel system cleaner in it cuz there may be some carbon keeping it stuck open or the injector could be cracked like mine were and youll just have to end up replacing them with new ones and also make sure the o ring isnt twisted and you can make sure it seats right by taking a small prick tool and runnin it around in between the o ring and the injector body.

[Bone]

I recommend replacing all the injector seals when you replace one. Take a small amount of vaseline and rub on all the seals then when you place them into the rail they are more likely to slip inplace then rip. You may need to bend the ears on the rail ever so slightly to keep more pressure on the seals. As far as the miss if the injectors are leaking it could also be sucking air and act like a vacuum leak. You need to fix one problem at a time. Just IMO

[Rennen]

aaarrrrrghhh :bash:

We've put 3 different O-rings on the injectors, and a different fuel rail, but it still leaks at the top of the injector where it meets the rail.

Does anyone know the torque specs to tighten the rail? I wanna just torque the fuck out of it so it make a stronger seal, but I am afraid to crack the injectors. I have the FSM, but cant find the torque specs for the rail.

Oh, thanks for all the advice so far, We cleaned out the the injectors with carb cleaner while they were off the rail. None of them are cracked. We are lubing the injectors with some ATF when we install them, and it seems to keep them from being ripped.

I also believe that the fuel pressure regulator on the new rail is causing the idle to be off, but we can't really find out until we get the car running.

-Matt

[Bone]

I torque them down till they tighten up against the bosses on the intake as tight as they will go. I have seen any that are not tightened down like that but there is a first time for everything. I believe the way it is made it will allow the tabs to bend some before it breaks the injectors. IMHO

[Rennen]

I've got em torqued down like that now, I was thinking of taking the 1/4" ratchet or a breaker bar to them....


It got superwindy outside where we were working on his car so we had to quit for today, but tomorrow I will pull the rail and see if the O-ring is still alright or if it was torn. I find it odd that it is the #1 injector everytime.

-Matt

[bobafett]

what are torque specs for the bolts on the fuel rail? i dont have my manual here, im stranded at my moms place trying to replace the injector o rings and seals... but i dont know what the torque specs are!

[khoadogg]

leaky KA injectors.... memories......

[rancid240]

are you installing correctly? Make sure to lube up the top o-rings generously with vaseline. Also, the fuel rail and injectors should be sitting perfectly when you bolt it down (i.e. dont force the bolts on)

[eyustfu]

i hate topfeed injectors, they kept tearing on me when i had them, i ended up using 2 orings up top on each of the injectors

[ledzeppelin240]

Just use some clean motor oil for lubing the o-ring, don't worry about using all that other shit. As for the torque of the fuel rail bolts I would never tighten the shit out of them. That is not the problem. I just finished fixing my leaky injectors and did not tighten the shit out of the fuel rail.

Make sure you are not twisting the injector or treating it rough when putting the fuel rail back on other wise you will run into some problems. If all else fails I would say the injector needs to be replaced if it still leaks.

[Rennen]

leaky KA injectors.... memories......



memories indeed....


What the hell possesses people to post inane comments on year and a half old threads? For those that tried to help regardless, thanks. But I am pretty sure my buddy doesn't even have that car anymore.

-Matt

[rancid240]

wow, didnt even notice the thread was that old.

thanks to khoadogg for giving the dead new life