Fuel in oil update.

[Tremblor]

So i took my truck to a 4.0L specialist, and he said the most common cause for fuel in the oil in one of these is one injector will not seal properly after the truck is shut off, therefor leaking fuel into the oil over time. The thing i wanted to know was, is there any way to determine which injector it is? any signs i can look for to see which one is leaking? Any suggestions would be greatly appreciated.

Also, i did a compression test and cylinder 6 was down 15-18 PSI then the rest, could that mean fuel is washing out my rings in that cylinder? Maybe replace the number 6 injector? any ideas...

 

[92exp4x4]

If i was to tear it down that far I would just replace them all.

Squirt some oil in the cylinder and retest. If the compression comes up then you know the compression problem is in rings and possibly related to the injector leaking. If not, the problem is in the valves. In that case its probably not related to the injector.

 

[patrick112390]

well that buddy of yours should have some sort of scan tool. on our ford IDS you can pull up all the injectors, and it tells you to cycle the key, and then watch which injector drops pressure=fuel leaking past it. when they all say 35psi and hold, and number 6 is going down..... you get the picture...thats part of the $89.95 diag lol

 

[freetodragdoors]

ids will not work with an obd1 truck also you can not measure injector flow through a scan tool if the the fuel rail does not have a fuel rail pressure sensor with a scan tool.

 

[patrick112390]

well crap loool i didnt look at the year. disregard that. i would say number 6 is your best bet without thoroughly diagnosing it with the low compression being your supportive evidence