Stumped by start/run problem

[azupcountry]

Evening all,
96 4.0 AW4. 240k.
After replacing cooling components back in October I have been enjoying a dependable worry free XJ on my 60 mile round trip commute..until..

A month ago while leaving home in the AM she stumbled with light throttle. Didn't make it out of the community. Borrowed folks extra car and started reading forum posts. Codes were 02 sensor and misfire. Replaced IAC. Ran great for a few days then same thing happened on the way home from work but the power went away, the idle got worse and worse until it died. Would restart but not stay running longer than 2 minutes. Had it towed.
Since then:
Both 02 sensors replaced
Intake air temp sensor replaced
Dizzy cap and rotor replaced (ran great for 40 miles-wouldn't restart next AM)
Coil replaced (mopar) no start
CPS replaced (mopar) started, ran great, idled high (1000rpm), stumbled with light throttle, slow 5 count to drop from 2k to 1k idle, turned off, no restart.
Tried putting old IAC back in, no start.
Not throwing codes (key turn method)
I do get fuel spurt at the rail but don't have a gauge.

I suspect that as before after a total cool down, it will start and run until I shut it off.

I don't have multimeter but can and will get one if necessary. Please let me know what you would do to track this down.

Thanks for any help

 

[azupcountry]

Update: Confirming easy cold restart this morning however..settled into normal idle and then stayed there for 15 minutes. Goosed throttle several times no stumble.
Was able to restart with no problems 6 times.

Last night during last start/run I unplugged and replugged IAC, Intake temp, and TPS - when i pulled this one it immediately died and CE came on code 22 which is coolant sensor but why triggered when I pulled the TPS?

Thanks

 

[Tim_MN]

Did you install Bosch O2 sensors ?

If your 1996 supports OBD-II, you should be downloading the four digit Pxxxx trouble codes instead the generic two digit OBD-I codes. The Pxxxx codes are much more specific about the possible faults.

Low battery voltage from a failing battery/alternator, or from poor electrical connections can cause stalling, a rough or erratic idle, and hard starts.


Is the battery fully charged ?

Have you Load Tested the battery and alternator ?

Have you tested the Throttle Position Sensor ?



Start with the basics, perform routine maintenance of the start and charge systems. Remove, clean, and firmly reconnect all the wires and cables to the battery, starter, and alternator. Look for corroded or damaged cables or connectors and replace as needed. Copper wires should be copper color, not black or green. Battery terminals and battery wire connectors should bright silver, not dull gray and corroded. Do the same for the grounding wires from the starter to engine block, the ground wires at the coil, and the ground wires from the battery and engine to the Jeep's frame/body. You must remove, wire brush, and clean until shiny the cable/wire ends and whatever they bolt onto.

Jeeps do not tolerate low voltage, bad wire connections, or poor grounds.