Rough Idle When Warm Or After Getting Off The Highway

[JT31]

so my mj runs good when its cold but once it gets warmed up it idles funny, the idle fluxuates a lot, and it also smells like I'm running very rich, i tried replacing one of the air monitors on the vacum system and even replaced my cat and muffler, only thing i can think of is the injectors maybe i have a stuck injector?

its an 87 with the renix with 225,xxx miles

 

any thoughts?

 

p.s i once burned a 1/4 tank of gas just idling for 45 mins

[HOrnbrod]

Replace your O2 sensor.

[JT31]

Replace your O2 sensor.

 

I don't have an 02 sensor

[cruiser54]

Sure does. If not, you will have high fuel consumption and idle issues.....

[JT31]

found the plug for the 02 sensor, but no 02 sensor :hmm: , guess i should put one in haha :yes:

[cruiser54]

found the plug for the 02 sensor, but no 02 sensor :hmm: , guess i should put one in haha :yes:

Yeah. Probably. Is the hole in the manifold plugged with something like an old spark plug?

[HOrnbrod]

found the plug for the 02 sensor, but no 02 sensor :hmm: , guess i should put one in haha :yes:

 

Where did you find the plug? On the exhaust manifold? Or elsewhere? Also, did you locate the 3-pin harness connector that the O2 sensor plugs into?