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Discussion Starter #1
Just got done putting the shims in the fuel pressure regulator and wiring up the knob and box, started it up and the thing threw 6 codes and started idling like I had a huge cam in it. All harnesses were tight and clips were all locked. If I take the box out of the loop and just run the factory wire on the back of the fuel rail, it idles fine with no problems. Does this mean I have a problem with the box. The codes it was throwing was fuel pressure too low at rail, crank sensor, cam sensor, egt, and two others I don't remember. Cleared the codes and not throwing any codes with the MP-8 box bypassed. Let me know if any of you guys have any ideas. Thanks in advance.
 

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I wish I could help ya but I saw your durango the other day out front of Sublime on Saturday...very nice!
 

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Discussion Starter #3
That means you saw it dirty. It's killing me not having that thing spotless. Hopefully they get the tuning done on it this week so I can start detailing it out.
 

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You might look at the plugs on the MP-8. Sounds like something in the wiring of the box isnt making a good connection. If that does not work i would contact TS. Look inside the actual plugs and see if any of the connectors are pushed in. Hope that helps.
 

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Tony are you positive you had the MP-8 connector completely seated on the back of the fuel rail? The first time I installed one I thought I had it connected and it ran like you described, ended up not having it seated all the way. It will run really rough or not fire up at all and throw codes if it isn't plugged in all the way.
 

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sounds like the same codes i had.... make sure the plugs are not backweards..... i had to flip mine around an voila!!!
 

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Discussion Starter #7
sounds like the same codes i had.... make sure the plugs are not backweards..... i had to flip mine around an voila!!!
Which plug did you have backwards? I doesn't look like they could go any other way with the clips the way they are. I should have had the clips on all the way because the little snap locked over. I know this because it was a pain getting it back off again. I'll do some more playing and see what it does. Keep the comments coming if anyone else has ideas. I'll update again soon.
 

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Discussion Starter #8
Plugged it back in, plugs snapped in just as tight as before, started it up and everything going fine. What the heck? The only thing I can think is maybe I had the factory plug backwards on the ts harness like lamoparpower suggested. I could have swore I made sure it was on the right way though because on the one side of the plug is the tapered tab where the clip of the other plug goes, and the other side is the oval centering pin that goes on the back side of the clip. Anyway, time for a road test. Thanks all for the help.
 

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mine did the same think ... un do the plug and do it again.... then un hook the bats no more cel
 

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Glad you got it figured out:thumbsup
 

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i htought mine was right also.... guess i missed something also... i was MADDDDDDDDDDDDDDDDDDDDDDDDDDD... then unplugged, repluged n said hell i guess i am that supid...:rof:rof
 

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Discussion Starter #12
Well, I guess I spoke too soon. It idled fine and no check engine lights, but went to drive it and I have no power, just a lot of surging. I disconnected the MP-8 wires and hooked it back factory, and it still does the same thing. So did I do something wrong with the fuel pressure regulator on the front? I took it apart, stuck the three shims inside the head of the nut, then spring, then disc with three holes, pressed back together and set the three holes. The only thing I did different was put two more dots on it to make sure it held together. Someone let me know if they had this problem as well. Thanks.
 

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Discussion Starter #13
Got it all figured out guys. After pulling everything apart again for the second time and not finding anything wrong, I noticed the boot off the intake to the intercooler was bypassing a little air. I don't know how it came loose from this morning, but somehow it did, and everytime I hit the gas, it would separate away from the intake a little and cause the truck to overfuel and surge. It's all good now. Definately notice an improvement in power even with the edge set to stock. Thanks again to all for your help.
 

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What size washers did you use or did it come with some? Should be gettin mine in the next few days and will install this week. I can do the valve shim now if someone can tell me what size washers. Thanks
 

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Discussion Starter #15
They come with the kit, so I wouldn't buy any.
 

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Hey rt4u2nv have you been noticing a good mileage increase yet at all or the same? When I get mine I think I might need your help so I dont have the same problems. I think some beers would be involved in the installation process:beer
 

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I wish I had had a beer drinking helper for my MP-8 installation. I had to make due with several folks here on the forum who typed me good suggestions.

Actually it isn't as hard to do as I made it.

First thing is the plug at the north end of the fuel rail is in very tight...use a 6 point socket to get it off and a long "helper". I did a little rounding on mine trying to get it off with a 12 point closed end wrench. To get the socket on you may have to work on the air horn to move it more than it wants to easily. After the plug is removed understanding how the nut works to remove the valve is key...again it isn't genius but I didn't get it right away.

Then the electrical connection on the south end of the fuel rail. This requires an 8 fingered person with exceptional digital strength and a very long skinny and flexible forearm. Not meeting that description I played with it for a couple of hours. I was finally able to get a very long 90degree bent nose needle nose pliers to grip the plug and push it backwards after getting the plastic catch undone with the other finger. Having done it once it was easy to redo it again when I decided to re-route the wiring harness a different way.

I didn't have any problem with the harness getting connected backwards. Didn't think that was possible but I seemed to have every other obstacle possible.

If I was doing it again it would be easy to do the whole job in an hour. First time took me several iterations over several days and a cumulative time probably closer to 5 hours.

A couple of beers for help from an experienced MP-8 installer would be well spent.


And I seem to be getting at least 3mpg better mileage according to the lie-o-meter.
 

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Hey thanks for the info pjesson! I would invite ya to help and drink some beers but it might be a long drive:lol3:
 

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Discussion Starter #19
Hey rt4u2nv have you been noticing a good mileage increase yet at all or the same? When I get mine I think I might need your help so I dont have the same problems. I think some beers would be involved in the installation process:beer
Sounds like a plan. I love the MP-8 so far. Driving around today I went from 13.5 MPG to a best of 16.3 MPG until the damn regen kicked on again. I noticed the regen kicks on and off more often, but I'm still getting even better mileage, and with a filthy air filter. Just think how good it will be when the 5" tbe gets here and after a filter cleaning. Let me know if you want to see how I did mine and I'll show you how I mounted the knob.
 

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Mine took about 1 hour to do. He's right you will have to move the horn out of the way to get a socket on there.

I used a long screw driver to pop the catch tab up on the connector then pushed it off carefully.

Using di-electric grease on the connector will make it go back on alot easier believe me I know LOL.
Brent
 
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