my 96 ram 5.9 is not running right at all. it was recently rebuilt has a slighlty larger cam, diff valve sprins, higher comp. pistons, shorty headers, a highflow cat and a flowmaster muffer, sct tuner and 4.11 gears everything else is pretty much stock. at idle it runs fine no misses it dosent run rough and it has fairly good low end torque the problem comes when i try to get on it...the engine just falls flat and goes nowhere it only does this if you put it to the floor and after it hits 2000rpm and once it hits 3500rpm it kind of sputters and falls all the way back down to about 2500rpm. then it goes back up to 3500rpm and comes back down. i can not get it to run past 3500rpm at all its almost as if a rev limiter is in place at that rpm. the other thing i noticed is that i hooked it up to my code reader and brought up the vehicle data and saw that the ignition advance is between 9 at idle (which seems fine) and 38 degrees when i open up the throttle (which seems like way too much advance) could this be why it dosent rev up past 3500rpm and has low power. another thing is that i threw a code which is number P0740 torque convertor clutch circuit open i really dont know what that means but the truck stalls out when i come to a stop sign and idels extremly low in drive or reverse. i did clear the code and drove the truck about 25miles and it has not since come back on. also i tried setting the computer back to stock with my SCT tuner and it did the same thing im really lost here i check all the obvious stuff no wires were unplugged or anything like that the engine just does not run right past 2000rpm and it stalls out in gear whenever i come to a stop just sitting at an idle it runs fine it idles at about 800rpm and you can definatly hear the cam and feel the truck shake but it runs well its not like its struggling to keep running in park or neutral it idles on its own just fine. im not even sure what to begin checking for a problem

 

Do you have a custom tune for that cam?

When the engine was rebuilt, did they address the intake plenum plate? Might wanna check out the Plenum thread stickied at the top of the forum, and see if that isn't at least partially your problem.

Nothing thing you can try is take the pre-cat O2 sensor out of the exhaust pipe, and take the truck for a drive, see if it runs any better. (you still have a cat, right?)

 

yes i have a custom tune set up specifically for my mods from hemifever, the plenum has been fixed with the hughes kit when i first bought the truck and yes i do still have the cat i will have to try unplugging the sensor

 

Not just unplugging it, you have to physically remove it from the exhaust.

 

I'll try that lol

 

Still does the same thing

 

how is your throttle body? dirty/stock? might need to look into a real good overall cleaning focus on the IAC due to sketchy idle. if stock, is it flowing enough air for this motor? might need to open it up, look at thefastman.com. could also be an ignition problem. coil most likely, but make sure plugs and wires are OK, TSB routing etc.. can you hook up a fuel pressure gauge and observe the readings while experiencing the problem? can your injectors handle the demands of this modified motor (most likely they can, but look into it.) Talk to HEMIFEVER about this. 'cause if your getting air/fuel/spark to this thing that's next.

 

Throttle body looks ok not sure what to check on the iac it seems like whenever I put it to the floor the torque convertor is completely unlocked because it goes no where at all it's just like being in neutral and it revs up to about 3500 then comes back down just like a rev limited but If I keep it at 1/4 throttle and under everything seems to work ok

 

Have you checked the TPS?

 

What exactly am I looking for on the TPS it's plugged in not sure what else to really check