Ok Here is the deal

sorry this 1st part is kinda short and dirty. I have a 99 dakota 5.9 R/T, i recently had a problem with the motor (ie rod knock) and i had to get another motor put in, A re built one. So 800 miles later i finaly get around to installing some of the stuff i had gotten for the truck. I put n a magnaflow catback dual exit, k&n FIPK "gen II" a Air raid throttle body spacer and a super chips tuner. Here is the problem i have. I put all that stuff (everything but the super chips in/on) and it seemed to run a little rough for about a 1/4 mile or so and then it smoothed out no problems. So about a week later i install the superchips programmer on the truck. I run it in the 87 octane mode. I jump on it and it all seems good all the way up till about 90. I dont go past 90 to often cause i really dont have any one to "run". So i fianly find me a stang to run and im doing about 50 on the highway. I lay the hammer down and it takes off good, then all of a sudden about 90-95 mph it shifts into im guessing it is its final gear, and it drops to about 3,500ish and then about 8,00/4k i hear a change in the rps not a knock or a ping its just like the power was being lost serously lost ( not just the 4k rpm normal power loss the r/t suffers from.) this is like a rpm slowing loss, so i let off. At this point im thinking ok maybe that was a fluke. So i go at it again and at the same rpm it does the same thing , but this time the check engine light flashes. I instantly shut it off and pull over. i open hood nothings out of the ordianry no smells or leaks the oil level is fine. So i turn it back on and the light was off. So i thought maybe it was the super tunner, so i set it back to its stock settings and get back on the highway and did another run. right before it shifts into final gear this time it does it again but not as bad it just kinda stayed at 4400 and had a change in sound and alot of power loss. Im just wondering what this could be from, and if it is a problem with the engine or maybe a part i have installed. and it desent do it in any gear but its last gear. Im thinking maybe its the throttle body spacer but i dont know. Any help would well it would just help. Thanks. Sorry i kind of threw everything all in one big lump but i am pressed for time at the moment. Thanks guys. and when i took off the throttle body to install the spacer i noticed a small 1/4 inch chunk of metal missing from in betweene the 2 intake/ butterfly holes.

 

first off,ditch the throttle body spacer, second superchips is ment only to work with stock set-ups ONLY, which means no exuast intake or engine modifications, i suggest checking your spark plugs from being fouled, they can cause a power loss , inefficient spark leads to ineffiecient power, hopefully you didnt damage the engine, i dont think so but its possible, she only ran rough in the beginning because the computer was learning the new parameters and intake and exhaust pressure to set up the right amount of fuel to inject into the cylinders, and since these mods free up restrictions, its not wise to use superchips since that was designed with all the stock components and ment only for that, and i dont know if this has anything to do with it but the R/T 360 is a beefed up version of the regular 360, so im not sure if that has a critical role with the engine running like crap, check your spark plugs and check your wires for resistance, i forgot what where the acceptable limits, and if they check out, go get the computer reflashed from dodge, good luck

 

Well yeh i am deff gonna take off the spacer, just sounds like a bad idea, and as the superchips goes, i havent read anything from anyone saying they have had problems with using superchips and other mods, but maybe thats woult it could be. And im starting to think it is a problem with shifting into overdrive or its last gear. Im going to do a fluid/filter change and flush, i have read on here how to do it so i dont think it will be that hard. and the motor runs to good for it to have damage no rough idle or anything, but ill check it all out. thanks.

 

Sound liek the Governor is kicking in, but not sure why at such a low speed.

 

What do you have the govener set at with teh superchips programmer? I think that might be your problem. (Good call Mike, I was thinking it but couldn't figure out why the stock govener would be so low. Then I realized he had the programmer, and it might be set that low accidentally)

 

well it asked me if i wanted to raise it and i said yes. i tested it out at lunch today and it still did same thing with everything set back to stock. I have ben reading something about some sort of Governor sensor or soemthing like that. Cause when it does the "change" it still picks up mph but its not as fast. I took out the plugs and they are dry and electrodes are a bit rounded and slightly has a ever so white tint on some of them. Nothing like its running to lean i belive it is.

 

If it is doing it on the stock tune obviously there is a issue with the truck. You did say the first time it through the CEL , did you read codes?
If it does it on the stock tune, do it again and then read codes afterwards.
Ron

 

The Engine light came on and then it began to flash. Then when i shut off the truck and re started it, the light was off. i rand a DTC from the superchips and it said none found.

 

your speed sensor is messed up. my 05 4.7 dak did the same thing. would throttle truck back at 99 mph. got rid of it and now truck tops out a 118 mph. dodge says with the right software truck will do 130 mph. but check the speed sensor. should be on top of the rear diff. also check to see if any wires got melted when the new motor was installed. check all the wires that run to the tranny and around exhaust manifolds