I'd order the blue hose kit, biggest leaks in the valley are caused by them. Preventative maintenance is my big thing. If it runs good now I wouldn't change it. Check icp sensor for oil in connection, check ipr for burnt connector which typically happens because of a fuel bowl leak, I'd check the tin nut on the ipr too as it should be snug. Buy a spare CPS as its your greatest threat of failure. Spare Maxi fuses due to if you didn't replace the fuel element heater in the bowl, sooner or later it will come unsoldered and will leave you stranded if you don't have a Maxi fuse to spare. I'm having to buy a western plow glow plug relay cause I blow mine up every couple weeks just cause the stock ones aren't rated for the amperage a set of new glow plugs can pull, I'd check batteries/connections as they can be causes for slow starts among the normal things, alternators typically are a regular thing with my truck and many others, the regulator typically craps out and that can cause no starts, hard starts, etc. Injectors wouldn't be the worry cause if it was stock and worked hard, it wasn't worked that hard cause these engines stock tuned will not wind up quickly or pull all to hard. Seven Tree for a reason.
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