Hey guys I just was wondering if I could get some help with a jeep cherokee I have. It's a 96 cherokee country. It has been running bad once it warms up to running temp. It misses pretty bad. When cold it runs pretty good. When it is warm tho it also has black smoke and kind of black wet **** coming out the tailpipe. I haven't had a chance to check the fuel pressure yet. The spark plugs are all black carbon like. They are not wet it's not oil. I have replaced the coolant temp sensor and the egr valve and the tps sensor. Also I had a cel on for the map sensor and I replaced that. Light is still on tho for the map sensor it says but I know that's not the problem because that is new. Any help is greatly appreciated. Thanks.

 

the problem is the map sensor circuit. Look up how much voltage its supposed to have for reference and check the ground. if you dont know how to then take it somewhere. The map sensor dictates how much fuel the ecu dumps according to engine vacuum.

 

Hey sorry it Took my so long to reply. I ended up getting a brand new map sensor and checked the voltage and it was right where it needed to be. I'm stumped. Anymore advice?

 

its a 96 pull codes or look at the live data

possible really bad o2 sensor causing a super rich condition

 

Ok. Yeah I have hooked it up and I'm getting the map sensor code still but I know it's not the map sensor. The voltage is right ad the sensor is brand new. I have another jeep cherokee all smashed up in my driveway that I might e able to pull the o2 sensor off of and put it on
This one. I'll give that a shot.

 

good luck pulling that o2 sensor off lol they like to weld themselves into place

could be a fault in the wiring going to the sensor that's causing that code still
cant tell you how to test it cuz I dont know the proper way to

 

Well **** haha. I'll give it a try and see if I can get it off. Running out of solutions. I might have to try checking all the wiring to the map sensor to make sure that is all good too I guess.

 

That's what i was trying to explain to you. Wiring to the sensor is the problem. So there is no way voltage at the map sensor is correct unless your pcm is faulty

 

Yeah I know. That's what I'm leaning towards. Either that or the ecu.

 

Map sensors should be 1.5 volts idle to 4.5 b at 0 in Hg vacuum