Running rich
09-26-2017, 10:34 PM
#1
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Join Date: Oct 2016
Location: Englewood Colorado
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Year: 1990
Model: Cherokee
Engine: 4.0 HO Swap
Running rich
Over the past 8 months i have replaced a few parts trying to solve a long crank issue (still havent figured it out). But after replacing these parts i have noticed a slight decrease in MPGs, Ive gone from around 16-17avg to 13-14avg. parts replaced have been... Spark plug wires, distributor cap and rotor, fuel pressure regulator, and map sensor. O2 sensor and spark plugs are less than a year old. When the engine is running even at temp it smells fairly rich. Thoughts?
09-26-2017, 10:43 PM
#2
CF Veteran
id reset the computer to relearn the new system. I think you disconnect the battery and touch the 2 terminals together and do a certain procedure to reset it but dont do that until another member confirms
09-27-2017, 07:17 AM
#3
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
OP: Check the line from the throttle body to MAP sensor.
Have you ever visited my website?
www.cruiser54.com.
I would do Tips 1,3,4, and 5 before replacing anything else.
And FWIW, The Renix system has a longer crank time than most any vehicles.