89 4.0 FI Cherokee...stalling and backfiring

[pbudzy]

I am new to jeeps and I just bought this 89 Cherokee it drove great the first 5 miles or so then started sputtering and backfiring then shut off....started back up drove 2 miles then same thing after that the engine was heated up and i couldnt get it to even stay idling...will turn over and fire so there is gas, but it won't stay running...I will try and replace the CPS as I have a little bit of mechanical knowledge..but..is there anything else I should be looking into?:bomb:

 

[MudderChuck]

When I first got my 89, it needed a CPS, a fuel pump ballast resistor (fuel volume was low), an O2 sensor, the connector for the transmission half of the TPS was full of oil and the ECU half of the TPS had a flaky ground. And the fuel was way old, the spark plug cables were mostly shot, the connection between the coil and the ignition module was green and really corroded.
All of which can cause what you described.
The alternator was marginal. as was the battery.
And the IAC was full of junk, which caused it to stall on occasion.

 

[pbudzy]

Yup part of the problem was the stinkin CPS after replacing it the truck runs ok, but stalls when i feather the gas lightly.....but not if i get on it....weird.
Also I found that there is 3 different sized tires on it once I looked at it in the light and if i try to get it over 35 mph it just about shakes me out of the damn seat onto the damn road...my guess is bad tires or unbalanced tires along with the fact there is a few different sizes which is never good. Anyways waiting on tires then I will update...prolly gonna do a bunch of fluid changes and brake bleed since the brakes are spongy and the fluid looks like choc milk in the master...this is gonna be a project but for 700$ total investment to have a running cherokee is cool with me...now the work begins...oh and I'm gonna need new front fenders as these were cut for 35's which i am switching to 31's so I think the regular fenders will be ok.:shock:

 

[MudderChuck]

My 88 was pretty ratty when I got it, now it runs and idles good, like new. Took awhile and was a project I actually enjoyed. Now I get to start on the exterior and see if if I can't make it look as good as it runs.
Clean out the IAC and see if that doesn't help your stalling problem. A few drops of oil allowed to run behind the piston often helps, don't try moving the IAC piston any, it can damage the internals or in the worst case launch the piston clear cross the driveway (learned that one the hard way, launched mine into the neighbors fish pond lol).
A sticky or malfunctioning EGR can also cause it to stall. The solenoid that controls the EGR defaults open, if it fails or the power is interrupted. If the EGR is open at or near idle the motor will stall.
Check the rear brake cylinders, pull back the rubber boot a little and see if fluid leaks out. Fairly common failure.

 

[pbudzy]

I think I need to buy a manual...to identify the IAC and the EGR...This engine is foreign to me.

 

[pbudzy]

Now that I can get it to 35 mph i have the DEATH WOBBLE..i know what to check just dont have the money right now....i know it needs to be dropped back down from its redneck 4" lift lol (you should see this hack job) and get a sway bar put in (yes its not there) and some normal tires (4 different sizes) oye....this ones gonna be some work.

 

[chevy3]

Change ur crankshaft and egnition coil.