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Old 03-08-2011, 04:42 PM
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macks-94yj is on a distinguished road
yj runs rough

hello there jeepers im new to this so here i go.. i just got a 94 yj 4.0 5 speed with 60k on the motor. when i start it up it runs fine and a few minutes later the motor drops to about 200rpm then goes back up 8-900 rpm. it will do that for a wile until it gets to operating temp about 180 to 190.. then the check engine light comes on and it runs like a champ.. and the gas milage sucks.. so far i have changed the iac,tps,air temp sensor,02, and the map.. and it still dose it.... i have also checked for vac leaks with starter fluid and the engine didnt race... so any help would be great thanks i got new plugs wires cap and rotor on the way from q tec...
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Old 03-08-2011, 04:45 PM   #2
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Location: Las Cruces, NM
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Garyk is on a distinguished road
check the water temp sensor, when the rpms drop does it sound like its getting too much fuel?

(Sold)1994 Jeep Wrangler 2.5L, Bestop top
/w steel half door and slider windows
5 speed, 2.5" lift, 31" tires,rack lights
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Old 03-08-2011, 05:09 PM
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just changed the temp sensor today at work and it still does it and when the rpm drops it is like it is about to die but then it jumps back up again
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