When engine is started cold , the engine will run smooth. I can drive it probley 15 -20 min when # 3 , third cylinder on the right bank starts to skip it will skip for maybe another 5-10 min then all out quit. to check this, here's what I did : while it was running and # 3 not firing I pulled # 3 Plug wire, no difference, then I unhooked the injector plug for that cylinder , no difference. then put a new spark plug into the # 3 plug wire and fired it up and the plug fired great , so I had narrowed it down to I am not getting fuel to that cylinder after it gets hot. Does anyone have a good explination for this? and what can I do to fix this problem
thank you for your help
Paul

 

is the injector all gummed up? i was just curious. i really dont know what to tell you. maybe you just have a fuel delivery problem or something. let me know

 

No I don't beleive the injector is gummed up, simply because it will run perfectly fine for a while. some one had told me a while back that there was a recall or something on these for some wiring that was had bad connections . I have a notion that I have a vaccum leak some where that is not allowing fuel to be drawn into the cylinder or maybe a bad o ring around the injector? who knows, it really is driving me crazy. however, thank you for your reply.
Paul

 

I would say that it is something to do with the injector or something with the fuel to that cylinder as you say it fires when cold and tapers down to nothing as it warms up. When cold and most cylinders are getting rich mixture that one gets just enough to fire, as it warms it gets enough to fire weakly, and when fully warm not enough to fire at all. I'm not sure about the wiring or computer causing just one cylinder to get a different amount of gas.

Do you see what I mean? Say that injecter put out just half the amount of gas. At rich mixture the others get say, 150% gas and that one 75% it might still fire enough to sound normal. Warmer, the others get still 110% gas and that one is just barely making it at 55% , fully warm the others get 100% but now at 50% or less it doesn't fire much at all. Grossly exaggerated of course but you get my idea. I just thought of that off of what you said it did.

 

I'd guess an injector too, based on your posting. However my reasoning is a little different. The injector is basically a solenoid that moves when electricity is applied (like a doorbell). The wire windings inside the injector may be breaking down and going "open" when things get warm. With the open circuit, the injector won't fire. Before you waste money and buy an injector on my assumption, you could do a resistance check of the injector with the engine hot (but turned off of course). Compare the resistance with another injector. If you have an open circuit, or a very high resistance, you have verified the problem. Good luck.

 

SJWOODY is right on target there, follow those instructions and that will tell you a lot more. I'm curious however why nobody rec'd plug wire/coil/ electrical it sounds to me that this may be your problem.. I assume there is a check engine light for cyl 3 misfire right? If so there is also a way to check injector fault on a Gensis diag computer. may be worth the effort. If yo can accomplish the exchange of say the #3 and #4 injectors see if it creates problem with #4 cylinder.