Another Injector O Ring question

[brewer]

Not too long after I put in my DIY efuel (SD pump, RR, etc.), I started getting a pinging sound (like a rod knock sound) from my passenger side. I've also noticed over time I've started getting some oil in my fuel filters. It runs rough (shakes pretty bad) at cold idle (pinging gets quieter as the truck warms up) and gets bad mpg. I've tried unplugging/plugging the UVCH with no luck. Still have yet to do a buzz test. I've also looked up youtube videos of it to see if I can match the sound to someone that's had the same problem, which seems close but I can't tell enough from those videos. As I've been doing some research, it sounds like I've lost an O ring? Truck has 146k

 

[silverpsd_06]

O rings would be where I would start also

 

[brewer]

Is it even worth it to run a buzz test or should I pull the valve cover and start plugging/unplugging injectors?

 

[silverpsd_06]

I wouldn't unless you think you have a weak injector but a leaking oil side to the injector will make it run pretty sporadically. You could pull the valve covers and look to see which injector is oiling less than the others

 

[brewer]

So I guess I better plan on buying injectors earlier than I thought and have them detuned.

The weird thing is it doesn't smoke blue at all; doesn't that usually happen when you lose an o ring?

 

[silverpsd_06]

Have you replaced the o rings yet?

 

[PSDEng]

All a buzz test will do is confirm that the injectors are working correctly electrically.

 

[brewer]

I have not replaced o rings yet.

I was planning on doing a buzz test before I pull the injectors to make sure its not an electrical/solenoid problem instead. So I just wanted other opinions on whether my thought process was correct.

 

[PSDEng]

Then sure why not, if you have the scanner there it only takes a couple minutes.

 

[mandkole]

The lower oil ring above the fuel half typically doesnt go like the top ring does. However, an oil ring leaking bad enough to put oil into the fuel should show itself with trouble building/holding ICP. pump DC% should be pretty high

 

[brewer]

Ah good to know.so would low icp explain the pinging sound?

 

[brewer]

Got the truck out last night. DC% was 75 at 2900 full throttle on my 100hp tune.passed the buzz test, and passed the KOEO test. It wouldnt stay running during the engine contribution part of the KOER test but as far as I remember thats an OBS thing...or rather even just an early OBS thing....

 

[brewer]

Well decided to just pull the trigger and replace O rings:
#5 and #7:

 

[zilla68]

what did you lube them with when you installed them?
hopefully that was your issue.

 

[brewer]

Just with motor oil. Going to change my fuel filters and monitor those.the knock noise is definately gone, though.

 

[Whytry]

That will do it everytime