just did timing chain ,water pumo and plenum repair started it up and sounds great but wont maintain a idle all vacum lines are hooked up pulled the distributor uot put marked it first what could it be

 

Did you check for vacuum leaks?Im new to these trucks,but most 10 or 15yr old vehicles have the potential to have cracked,worn or broke vacuum lines an hose's.Taking them apart an putting back together would up the odds of this happening.Maybe spray some ether around an see what ya come up with..If you have not done that yet..Everything I have owned in the past 10 years has been avg 10 to 15yr old at the time of my ownership..I had some sort of minor vacc hose issue with all them at some point

 

Must be posting from phone...just guessing by spelling...

You pulled distributor? If yes, then you need to have fuel synch reset with a computer.

And +1 on checking the vacuum lines again. Those small plastic lines get brittle and crack and break.

 

explane fuel sinc to me please

 

These engines are sequential port injection. What that means for you is: Each injector fires at a specific time in the cycle. Either shortly before, or while the intake valve is opening. In order for the engine to know the correct time, the cam sensor in the distributor has to be set correctly, (and that is what is known as fuel sync) If the injector fires too early/late, you don't get a complete burn, you end up leaving a fair bit of power on the table, and it won't pass emissions, since it isn't running as efficiently as it should. Need a scanner to set sync.

 

more details and symptoms.

one opinion:
If you do not have a scanner that can do this, then pay to have the dealership do this. Some of the symptoms that the sync signal is incorrect, you will get back firing through the intake manifold; vehicle will not idle or you will get major
detonation at light loads causing the vehicle to lose severe power over 3000 rpm.

another:
you can get close, but not perfect using a digital volt meter.

copied from here...http://www.justanswer.com/dodge/2b9v...-2l-motor.html

The first thing I'd like to do is check the rotor play. Pull the cap off the distributor and turn the rotor by hand. If it moves more than 1/4" by hand it shows there is wear on the distributor drive gear and it would need to be replaced along with the bushing that holds the distrtibutor shaft in place in the block.

Over time between timing chain stretch, cam and distributor drive gear wear, the sync will slowly change. The ignition timing on your truck is electronically controlled by the engine controller. Turning the distributor does not change ignition timing, but getting it in the right spot is very important. You want it as close to 0 as possible, when you start getting too far each direction you can have driveability problems or even the spark firing to the wrong tower in the cap. Putting the distributor in the right position on these is called "setting sync". This is best done with a dealer scan tool, but can be done with a voltmeter. You are setting the rotation so the cam sensor (inside the distributor) toggles its signal voltage at the perfect time. Here is the procedure to set the distributor on your Jeep without using a dealer scan tool.

Connect a voltmeter to the pickup plate connector by carefully back probing the connector. Connect the positive lead to the sensor output pin (pin 3, either a tan wire with a yellow tracer or a gray wire, depending on vehicle application). Connect the negative lead to battery ground.
Rotate the engine clockwise as viewed from the front, until the number one mark piston (TDC) on the vibration damper should line up with the zero degree (TDC) mark on the timing chain case cover.
Continue to rotate the engine slowly clockwise until the V8 XXXXX XXXXXnes up with the zero degree (TDC) mark on the timing chain case cover. The V8 mark is 17.5°after TDC.
Make sure you don't back up and turn the crank counterclockwise if you miss your mark. If you do, back it way up and then come back clockwise. You need to keep the engine turning in normal rotation to keep timing chain slack in the correct spot, or the cam/crank relationship won't be in their natural state when you set sync.
With the distributor clamp bolt loose and the ignition switch in the ON position, rotate the distributor slightly in either direction until the voltmeter switches between the sensor transition point of 0 and 5 volts.
Adjust the distributor as close as possible to either side of this transition point and tighten the distributor clamp bolt

This is all there is to it, pretty simple. It's not quite as accurate as with a DRBIII, but it's pretty close.

 

I marked the distrubtor before removeing it and put it back to were it was truck is pinging or knocking at very little throttle in drive had to remove distrubtor cause i had a broken intake bolt way in the backand was in the way when removeing bolt

 

If i bought a sct tuner would? that fix it?

 

No it won't, you need a scanner capable of resetting the fuel sync. And what if anything did you do about the o2's and cat? Was the plenum gasket blown?

 

had some slight oil in there probly from pvc one little bulge but gasket still held o2s are new with exhaust did the plenum plate fix anyway new cats too