so after an ecu a blown 120 amp fuse in the fuse box, a small vacuum leak and a 3rd iacv, its running, pings a little bit now but it still wont idle. im lost

 

Any codes? Does it just idle too low, and stall?? Did you reset the PCM after replacing IAC? Tested the TPS?

 

no codes starts high then when it lowers back it drops below a grand sputters a little then dies, i never knew i had to reset the pcm or how to do that, Throttle positioning sensor im still trying to figure out where and what it is, could it be a carbon build up, tb was disgusting so i cleaned it and ran fuel injector cleaner through now its smokes when it fires up, drives great just stay on the gas

 

To reset the PCM, just disconnect the battery for a few minutes. (and maybe turn the headlights on. Turn 'em back off before hooking the battery back up.)

TPS is on the drivers side of the throttle body. Three wire connector. One is five volt supply, one is ground, the third is signal back to the PCM. (modifies voltage.) Should be less than 1 volt with throttle closed, and greater than 3.5 at wide open.

If you keep your foot on it, will it idle around 700 or so when fully warmed?

 

sounds to me that the pcm just needs to relearn idle. our jeeps battery got drained because of my daughter playing with the map lights, and left 2 on without us knowing. jumped it, and would not idle, unless you kept your foot on the skinny pedal. after a few starts it went back to normal idle.

 

it was driving great for a little over a week, still wouldnt idle on its own, but no other problems. the temp gauge went out, overheated blew gaskets. intake maifold upper and lower was done. started up ran smoked bad now and shakes a lot more. must be a head gasket also..idled on its own finally though

 

ok it seems i had a cracked block , blown piston rings, blown head gasket..pretty much toasted the motor..ive been looking to replace the 5.2 l engine but the junk yards around here have very high mileage engines so i found a few on the computer for around $800 with about 130k miles and a 1 year warranty..any other suggestions??

 

I would rebuild one if i were you. Its the only way that you know for sure what your getting into. If you strip the motor down, buy all the parts and then take it all to a machine shop to have it all assembled the. Your looking at about $1000 maybe less. Ive got about that into mine but i had to buy a new crankshaft which was almost $300 in itself.

 

dont really have the time to wait for a complete rebuild at this point my company has veen without a work truck for almost 2 months, its either time for a semi permanent fix or junk it and buy another truck. im leaning toward the used motor and eventually will shell out the cash for a crate motor after income tax time...or thats the plan

 

Never tried them so Im not sure. But Ive seen the site thrown around here a few times.

http://www.precisionengine.com/rebui...ler/index.html