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4.0 power loss

ILLXJ

NAXJA Member
NAXJA Member
Location
Louisville, IL
98 4.0 with 66682 miles will start and idle fine. Drop it in gear it some times spits & sputters and other times will take off fine. When it does take off it will only go 100 to 200 feet before RPM's drop. Check engine light does not come on & I have not been able to get any codes to flash. Any advice? TIA, JIM.
 
Any difference in hot/cold engine? It sounds like your mixture is too lean. That could be an O2 sensor or coolant temp sensor also. Are you able to drive it at all? What have you done so far?
 
Had a similar problem on our 89YJ, was the neutral safety switch, sometimes it would just die, sometimes it would run, sometimes both. Made comint or going somewhere an adventure.
 
Much worse when motor is warm. Checked cap & rotor, both bad. Spark plug gap at.050. All of this getting changed in the am, will see after that. thanks again. JIM
 
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