KOER, and KOEO test | Ford Explorer Forums - Serious Explorations

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KOER, and KOEO test


September 14, 2009
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City, State
Fayetteville, arkansas
Year, Model & Trim Level
'92 Explorer 4x4
hmmm, did the KOER test. All that it keeps saying is code 73, which from my understanding means "User Error", somthing to do with the full-on throttle phase not initiating correctly at the final part of the test? Ive done the test 5 times, and each time i push the gas pedal all the way down, which is reving the engine to around 5-thousand RPM's and im quickly letting off, like was suggested... This is the only code, and its repeating itself twise to me. Im not sure how i could be doing anything wrong? Also with the KOEO test, all im pulling is 111, and 111, than another 111, 111??? Im guessing this is saying that there is no reported problem? Engine is FINE? Question, If the alternator is going bad, would a code be able to be pulled showing this? Ive noticed somthing while tinkering with things today. While the engine is warmed up, if i turn on the heater it causes the engine to start running horribly. Now usually if the engine is warmed up the engine runs smoother, and better, unless i turn on the heater. Its instant, just as soon as i turn the heater on there is a drop in the idle speed, a swift surge or drop on the amp/volt meter gauge thing (aka battery gauge on dash) and the RPM's drop and started fluctuating just like they do when i first turn on the vehicle when its cold and not warmed up yet??? I repeated this over and over and over, untill finaly it even made the engine die once. I even started to notice a white smoke coming from the exhaust as the engine was acting up like this. My guess is one of two things... Either the Alternator is going bad and when i turn on the heater it is pulling a draw on the system that it cant handle, or there might be a short somewere?? COULD THIS BE the main issue ive been faceing the entire time? Would this show up on the KOEO/KOER test? Thanks, Jason.

quick method of telling if the alt is going bad or is bad is if you do not get 13-14 volts at idle with it all hooked up ( battery and alt) ...the other is ( not sure if this will harm the computer tho ..memory wise ) is to start the truck and dis-connect the battery while the engine is running ...if the truck dies right after you disconnect the batt then the alt is bad because now the engine has no way of getting voltage to fire the coil pack .

got to ask tho when you turn on the fan ....is the a/c light on when you do this ? if so then it may be a a/c related problem .once the fan is turned on and pushed in to activate the a/c system it turns on the relay for the a/c ...maybe the a/c relay/ compressor is damaged or the clutch is have a hard time turning over putting strain on the engine at idle.

big if for the a/c system being the cause but just wanted to rule that possibility out of the way .

Well, if you have the heater core "on/off" thingie (can't remember what it called ATM), I'm sure it's vacuum controlled, and when you turn the heat on, if that control line is damaged/missing then you would have a vacuum leak....all I can think of.