I have replaced my fuel filter twice in the past 10k miles just to be careful. The problem is primeing the fuel system. i dont want to pour the old fuel into the new filter. is there a jumper i can make on the relay?

 

Why not just get new fuel in a can or jar for that matter.

 

not sure how new your truck is, but current ones have ignition key sequence to prime engine after filter change or running out of fuel and re-fueling.

attempt to start, if doesn't start and run, let key return to on and leave on, lift pump will run to fill filter housing...

 

2nd gen isn't quite that simple.
Won't work if you totally run out of fuel, but for changing the fuel filter, you bump the starter (without starting) and the lift pump runs for 20 seconds, more than enough to fill up the cannister.
If you push in the valve stem on the VP shraeder test port while doing this, any air will be purged out.
Hard to do with only one person, so I leave the fuel filter cannister lid slightly loose to let the air out, just have to be really quick tightening it once the fuel starts spewing out.


phox

 

You could consider running a pre and post gauge to monitor the pressure difference on either side of the filter.

 

yes u can make a jump wire i did it on mine its the yellow or orange wire on the lp dont leave it on there for more than 30 sec or it will trip a code

 

No word on the yr your truck is but on my '99 I finally put a guage on. I put a manifold system where I have a pre and post filter tap w/ valves so I can check the diferential. More then a couple of pounds and the filter is changed. The newer ones I hear have plastic mounts and no built in tap sites. You would have to mod the banjo bolts.
I have to get some electro geek to make me up a differential guage so I have a single readout of pressure drop across the filter. Maybe a neat set of LEDs .
If I get a workable plan I'll post it.