i own a 99 cherokee automatic 4x4 with the 4.0 it has about 135k on it and recently it has been giving me some issues. when i start it up after its been sitting for a while it starts and runs fine for a minute or so but then it will start missing for about 45 seconds unless i shut it off and restart it then its fine..i dont think it has had any sensors replaced on it and any help you could give me would be much aprecciated thanks in advance

 

i read somewhere that it could be a 02 sensor does this make any sense

 

also where would they be located at

 

it might be your vacuum lines

 

Can't help too much Bob but a '99 should have an OBDII system on board - have you tried pulling codes first?

 

no i dont quite know where or how to do that and if it were a vacuum problem it wouldn't go away just cause i shut it off and restarted it would it? im pretty new to everything fuel injected and with all the computer stuff..i am used to old carburated cars and stuff of that nature....

 

what do you mean by the engine is missing like it sounds like there isnt all the cylinders going?

 

yeah pretty much it wont do it as bad when its in neutral but when you put it under load you can really tell it so i guess it does sound likes its droppin a cylinder

 

intake manifold gasketit might be that

 

wouldnt it do it all the time though

 

it might be your plug wires. one of them might have a bad spot in it or on it

 

yeah i havent replaced them and i doubt they ever have been replaced...roughly how much do they usually cost

 

you can get a whole tune up get from jegs for under 60 bucks

 

oh and the check engine light does NOT come on, i dont know if this matters or not just figured i would tell you everything i know

 

if you think its a vacum leak get some carb cleaner and spray it on the lines and if it has a bad line it will suck in the cleaner and start ideling rough. i would start with a tune up tho