So i just did a complete tune-up on my cherokee. New plugs, wires, cap/rotor, fuel filter, o2 sensor, map sensor, fuel pressure regulator, seafoam, also cleaned throttle body and iac sensor.

Now it still idles bad(sounds like its spitting), get about 11.5mpg, and also exhuast smells like gas.

HELP PLEASE.

 

help please

 

cylinder compression? Just wondering, that happened to my friend's dodge. He had to put in new piston rings. If some of the gass smell goes away when the engine is hot then it could be the rings are too worn and they are just making a better seal when they expand when it is hot. just a tentative thought though.

injectors?

 

not leaking oil on the spark plugs and not blowin any blue smoke.

 

Does it feel like it has a loss of power? Cat could have broken up and have a partial clog.

I recently had the same issue.

 

Change air cleaner and then clean your IAT sensor.

Use this for reference:

https://www.cherokeeforum.com/f51/budget-airbox-mod-iat-relocation-2599/

Have you changed your thermostat?
Is it a 190* or have you made the same mistake as others and switched to a 180*?

 

Cat is aftermarket high flow and i just bought a k&n intake system

 

i havent changed the thermostat out.

 

intake air temp. sensor= check; Upstream O2 sensor replacement (this is most likely only the cause if it runs at a higher rpm for the first 2-5 minutes of idle); very unlikely but try testing the idle control motor or the idle control valve---one last thing the manifold absoulut pressure sensor or the MAP sensor. you could try to see if the problem abates if you reboot the ECU by disconecting the battery too. (however i really don't like this meathod of "fixing" problems 'cause it erases the error codes that have been stored)
just a few thoughts again.

 

thanks again. i replaced the o2 sensor and the map.

 

Similar problems, did the Map and o2 senser fix it for you?