I have a 1999 Cherokee sport with automatic 4.0.. I just bought the jeep after it sat for a year. I put every type of cleaner and changed every filter and oil in the darn thing. So, it starts fine but smokes pretty bad out of the tail pipe. At idle, the RPMs move up and down a bit. The smoke from the tail pipe is white and happens on and off. It also sputters some. And when I'm going and come to a stop it will sometimes stall and die, and which it's pretty hard to start afterwords. Check engine light is on...
Please help get me on the road!

 

White smoke would be coolant. The combination of the smoke plus the stumbling sounds like somewhere you've got a cracked water jacket, head gasket, or something like that. Watch your coolant level and see if it slowly drops as you go. You can also pull a spark plug and see what is on it. Whatever is being burned in the cylinder will leave residue/remnants on the spark plug.

 

sounds familiar .. mine had grey (looked white in flashlight) smoke after purchase .. drove it 30 miles to home

cat was toasted

when somewhat cool .. by hand, bang on cat converter .. does it rattle ?

if so .. toast .. bang on it when warm .. if cat insides are melted .. easier to tell when theyre loose from heat .. think they may fuse back together when cool

I replaced O2 sensor / new cat & muffler .. then I changed the oil after .. all was good .. passed emissions

hopin you got a "pass emissions / smog/smoke test" included in sale .. i did .. my seller was kind enough to reimburse new cat & labor

 

Really think a cat could do this? I'm leaning toward head gasket but cat would be nice.

 

if its emissions related .. yes


new cat / new muff / new o2 sensor .. smoke gone .. after owning this 3 months, found it has no EGR .. was left out on rebuild .. Im running kinda rich

if its really white smoke you have .. that you can see in rear view mirrors .. probably coolant

you'll smell it too .. smells sweet kinda .. like stomach turning sweet, will burn your nose hairs

I had a weird knocking sound also, shifting like crap .. until I changed oil after the exhaust was fixed .. fuel laden oil i assume .. new TPS / adjusted throttle cable with new oil .. been good since

 

I also have weird shifting! But the smell is kinda minty sweet, and smoke comes from engine bay too

 

you may have a severe clogged cooling system .. contributing to this .. especially sitting for a year

Mine smelled horrible .. interior / engine

minty smell is clean coolant burning off in engine compart .. horrible smell is cooked heater core or radiator (old brown coolant) .. it smells very bad when hot .. My old radiator when hot .. could smell it 15 feet away .. glad I saw seepage from the fins .. replaced it

you check for coolant leaks ? or super hard / pressurized coolant hoses?

After my exhaust .. did a shop job cooling flush .. flushed everything good / new rad .. it was very clogged, saved this jeep from certain death

check that out for sure

sounds you may have a jeep similar to mine .. PO didnt do squat in maintenace .. sad .. go thru everything !!!!! save her, the 4.0 s seem to hold up to abuse .. but sounds yours needs some lovin .. as mine did

 

Find out what the code is.

 

@dogkatcher..
Yea the water+coolant was leaking from 2 freeze plugs and the large hose going from the radiator to the engine had 3 little holes jetting water while running. I changed the freeze plugs and RTV'ed them and changed the hose. Havnt cranked it yet since though

 

Ok, did a coolant change, changed plugs and wires, started the jeep... Smoke, spitting fluid from the tail pipe. Pulled the plugs, coolant all over the 3rd plug back

 

It's a cracked head... Fml

 

Not to big a deal it's right on top imma have to pull my head off to

 

$$$ is the problem

 

I here ya there. Is for me to

 

I Gota parts jeep that was to be sold in literally hours. When I found out the head was cracked I called off the sale. So now I have a spare head