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Fumble under 2k rpm

Maxwell

Active Member
Here's the lowdown. Jolene (my 93 LX) just started losing her mind. Under light and heavy acceleration, worse when cold rather than hot, she wants to fall on her face under 2000 rpm, anything above 2000 she runs great no stumble misfire etc. Also idling during a cold start she almost stalls out. No CEL although there may still be codes present (haven't had a chance to pull any yet) has anyone had this issue?
 

John2002

Guest
I can't tell you where to start but the mass air flow and the idle air control is where I went first on my 89... My IAC was really carbon'd over and the MAF meter
seemed to be sending wrong signals to the ECU. There isn't much left to check, loose plug wire or plugs??? My throttle plate had lots of build up on the side that faces into the air plenum. I tried E3 spark plugs once and after I put them in it seemed to run terrible at start up and never made any so-caleed performance gains..Went back to MotorCraft plugs and it started and ran much better...
 
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