CaptainFill

iTrader: (1)

Hello,

I replaced my KS and hoping that would improve my car a lot acceleration-wise. It didnt do much so I was a little disapointed. When I floor it from a stop its still really pokey.

Anyways... I hooked it up to a scanner to check for any codes and run a few tests. No codes came up but when i did a fuel injector shut off test for each cylinder it became obvious cylinder 4 wasnt firing (front middle, looking in the hood).

I scoffed it off and figured oh well its gotta need a new coil because it is a seemingly common problem. Just to check it out i took out my plug (new plugs) hooked it on the coil and started my car to see if it was firing.

The plug was firing and now it is leaving me stumped. Upon removing the plug there was a bit of oil on it, im sure its not a healthy amount but with a car that has as many miles on it as i do, its prone to have some. And stupid me... i didnt smell the plug for gas...

Now I am thinking its my fuel injector for that cylinder, or a very weak coil (common?).

I also did a compression check, around 125psi, not bad, not great.

So now im just thinking, is it possible that it could be the injector? Can i take mine out and clean it? How do i clean it?

Thanks!

pmohr

iTrader: (26)

Either the coil (sometimes they fail under load, i.e. WOT, and not at idle or low speeds), or the injector. Did you resistance test the injector? If it passes, it means it's either bad or good. If it fails, it's bad. I'd say pull the fuel rail, crank and watch the spray pattern, ideally it should be a nice cone shape. It could just be clogged up.

Try a fuel system cleaning product or service, just don't soak the injector in any kind of solvent. Also, check the harness to make sure it's okay, or if there's corrosion on that injector's connector.

Eric425

Of course it's possible it could be the injector. Why don't you put a screwdriver to it and listen to see if it's ticking, and do a resistance test with an ohmmeter? Or switch up the coils with one of your other known good ones and see if you get the misfiring in a different cylinder.

CaptainFill

iTrader: (1)

Ok thanks! I will first check for the injector "clicking"... How exactly do i check that without taking it out?... just listen to it or feel a vibration by placing a screwdriver on it?

If it is bad, can i clean the ends with something like carb/fuel injector cleaner on a towel?

Eric425

Just put one end on the outer case of the injector and the handle to your ear and you should hear it. If you're having trouble hearing it, switch up the ignition coils and see if you still have the problem in the same cylinder. After that, it should be pretty safe to assume that the injector is the problem.

CaptainFill

iTrader: (1)

Well it is the fuel injector, its not working at all. I cant get the actual injector out... does it just pull out with a lot of force?

CaptainFill

iTrader: (1)

Anybody know of an easy way to remove the injectors? Ive got the cap off... but popping the injector out is a little tricky.

Eric425

Yeah, just pull it out with a lot of force. You're lucky that it's the front bank injectors, which are way, way easier! Man, it took me forever to do the rear. I did one with vice grips. After you've disconnected the injector from the plug and have the top off, you just clamp down on it hard, twist from side to side and pull! I found it easier to clamp down on the rectangular top of the injector rather than the plug which sticks up, since the force you apply can then be directly upwards. A second option is to hammer the end of a chisel, punch, or a screwdriver into the plastic top of the bad injector, and lever it up. Try not to contact the metal seat of where the injector is in, or if you damage it enough it might not seal properly when the new injector is put in.