How do you clean an mpi fuel system from old fuel?

Once you figure it out let us all know the results. My father inlaws truck has been sitting for 15 years and eventually I'm going to have to tear into it and get it started. It's a 99 dodge ram 6 banger with zero body rust.
 
A top end cleaner like the Lang TU-470B

SnapOn of course makes a really sweet one and it's as expensive as you'd expect, but they pop up second hand on ebay for semi-reasonable prices.

My Lang was least expensive thru Zoro with 10% code

These are also crazy handy for the (admittedly rare) cases of bad gas -- just fill with normal gasoline and see if she suddenly runs fine. I had a real-world case of this on an '11 Forester.
 
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GRUMPYDUDE2 said:
If it will start and run as is, I would do this first.
"Dump a bottle of Techron in a fresh tank of gas"
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I run the boat regularly on the trailer, but its like if you dont actually take it out on the lake and run it up in the rpm range is when i have issues with it not wanting to accelerate past like 3000rpm unless I dump it in the lake more often. Runs great on the garden hose, but i dont know If its going to have a problem until out on the lake. Its so odd. Last time i just kept it around 2000rpm for a while in hope that would clean things out, then after doing that for a good 30 minutes it went back up to my usual 3800 rpm cruising rpm. Although it did seem a bit slow for the rpms to come back down which I thought was weird.
 
The motor guy said:
I run the boat regularly on the trailer, but its like if you dont actually take it out on the lake and run it up in the rpm range is when i have issues with it not wanting to accelerate past like 3000rpm unless I dump it in the lake more often. Runs great on the garden hose, but i dont know If its going to have a problem until out on the lake. Its so odd. Last time i just kept it around 2000rpm for a while in hope that would clean things out, then after doing that for a good 30 minutes it went back up to my usual 3800 rpm cruising rpm. Although it did seem a bit slow for the rpms to come back down which I thought was weird.
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Ahhh... a boat, you should have mentioned that.

Limited use things (like boats) like to clog injectors. I'd start with pulling them and having them serviced. I just ran the injectors on my merc 260 outboard and I had 2 that were pretty bad dripping at 390cc/minute while the good ones were at about 490cc with a good spray pattern. I changed the baskets and cycled them in the ultrasonic a bit and got them all to within about 1% of each other at 495cc/min at 40 psi.

If you don't know when it was last done, I'd get the injectors serviced, start there. Change your fuel filter, and see what happens.

I haven't done it yet, but I'm going to plumb in a fitting to run the engine off of an aux. fuel tank and use that canned $20/gallon stuff with a 3 year shelf life from home depot to shut it down when it's gonna sit for more than 3 weeks or so. We have E10 fuel here and it's mostly garbage if you don't use it within a week or so.
 
The motor guy said:
I run the boat regularly on the trailer, but its like if you dont actually take it out on the lake and run it up in the rpm range is when i have issues with it not wanting to accelerate past like 3000rpm unless I dump it in the lake more often. Runs great on the garden hose, but i dont know If its going to have a problem until out on the lake. Its so odd. Last time i just kept it around 2000rpm for a while in hope that would clean things out, then after doing that for a good 30 minutes it went back up to my usual 3800 rpm cruising rpm. Although it did seem a bit slow for the rpms to come back down which I thought was weird.
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What motor?
 
Arc said:
Once you figure it out let us all know the results. My father inlaws truck has been sitting for 15 years and eventually I'm going to have to tear into it and get it started. It's a 99 dodge ram 6 banger with zero body rust.
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You don't use the suffix "-banger" to describe a 6 cylinder vehicle. It's a 6 "pot". Four cylinder cars are termed -bangers because historically they're not as smooth as sixes.
 
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ripcord said:
Prevention, prevention, prevention. Put fuel treatment in every season and never, ever run it on last year's gas. Drain them tanks.
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118 gallons. Wish I had an easy way to. Maybe just pull the return line off and fill up some 5 gallon cans
 
Jarpin said:
You don't use the suffix "-banger" to describe a 6 cylinder vehicle. It's a 6 "pot". Four cylinder cars are termed -bangers because historically they're not as smooth as sixes.
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I drove the old dodge a few times many years ago and it was a banger. Looks good on the outside but the engine was pretty rough.
 
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