Trying to figure out which injector (or cup) is pissing fuel into my engine...

[dieselcruiserhead]

Hi guys,
I'm having a fuel dumpage issue. One of my injectors or fuel cups is pissing fuel into my system. I'm pretty sure its not any of the injectors on the drivers side now (though it could be a cup).

Is there a way to check to see what injector it is? Would a cylinder contribution test (is this the same as a buzz test?) be able to tell me this?

[tubular031]

I dont know the answer.... Just wondering, what makes you think you have a leak?

Maybe call your injector supplier of choice and tell them what is going on and see if they have any advice?

[dieselcruiserhead]

Injectors have all been tested or rebuilt. I acquired a bunch in a parts 2001 Excursion engine I acquired, I've had them tested and rebuilt and/or re o-ringed as required. All injectors on that side are fine.

The reason I know I have a leak is mileage has been aweful (about 5 mpg) but most importantly there are huge clouds of white smoke coming out of the exhaust: unburnt fuel dumping in. It only turns black when there is combustion. In this case there is too much fuel for combustion and it is being inserted at all times not at DTC.

I figured out the problem. I replaced that head just recently and have been having the problem since. The injector cups have coolant on the other side of them to keep the injectors cool. I guess when you have the head hot tanked (pretty standard in the head rebuilding process) it shrinks and/or causes problems with the copper cups and they are supposed to be replaced. So that is the problem -- I was unaware of this. A tell tale problem is fuel in your coolant. I looked at my coolant tank and sure enough there's about a gallon or two of fuel in there. 55psi of fuel pushing into the 12-20 psi coolant system. I also had my "water in fuel" light turn on as well.

So now I know.. I'm taking it into Ford as they have a special tool for removing the cups without removing the head. I'm also going to have him run a diagnostic on it as well at the same time...

thanks,
Andre