leaky injector? 91t - Toyota Nation Forum : Toyota Car and Truck Forums

jesse0880 · 08-28-2009, 03:54 PM

I think I have narrowed down a t/s problem to a leaky #4 injector. To confirm it, would it be worth swapping the #4 injector with another cylinder injector to see if the symptoms with the #4 cylinder change. pretty much, the problem is lack of power and when I pull the #4 plug, its black (tried new plugs).???

should I swap them or not?

***MR2Jedi*** · 08-28-2009, 04:37 PM

Is fuel leaking from the fuel rail?
Black fouled plug indicates oil.

Once you remove the injector, you will need a new O ring before you install it. Might as well just change all the Orings and see how it does.

TheEngineer · 08-28-2009, 08:59 PM

you sure its not a valve seal or something. Have you done a compression test on the motor. Typically if the injector is leaking more fuel into the chamber then you will get a cleaner plug. Because there is a very rich condition with excessive fuel. I have that problem and my plugs were totally clean.

GeoffBooth · 08-29-2009, 03:38 AM

Is the plug just black or black and wet?

Don't be in a rush to pull the injectors. Try listening to the injector through a screw driver while the engines running. See if it is ticking like the others. It could be a bad connection to the injector especially if they have been messed with. The connecters get brittle at this age.

Probably a bad plug lead. Replace it or maybe switch it out with #3 if it's long enough. See if the problem moves to #3. Could also be the dis cap and rotor or even the ignition timing.

If all the cheap simple things fail. A compression test because it could be the head gasket etc. Seems like everything bad shows up on the #4 cylinder on these cars. Any overheating problems?