EEC-IV codes 327, 337 & 538 | Ford Explorer - Ford Ranger Forums - Serious Explorations
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EEC-IV codes 327, 337 & 538

August 23, 2004
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Goose Creek SC
City, State
Year, Model & Trim Level
1994 Explorer XLT 2 WD
hi, I bought an EEC tester - got a few codes:
KOEO hard code 565 (saw in here I should have the canister purge circuit tested)
KOEO stored: 327 (EGR valve position sensor, Pressure Feedback EGR sensor OR EGR Pressure Transducer - signal voltage too low)
KOEO stored: 337 (same as above only too high)
KOER 538: Insufficient RPM change during Dynamic Response Test. or, Invalid cylinder balance test - throttle position movement. or, Invalid cylinder bal test - cylinder identification problems.
I believe the KOEO codes are wiring probs. I got a carfax last yr and see my X was in 2 crashes. I see where paint is different on left fender under the hood & have seen paint peeling off the roof near the rear door. I assume it was a front and a rear crash. Carfax couldn't clarify. I know there are intermittent wiring probs w/windows getting stuck up or down. HAHA the other day I pressed the up button on my stereo and the pass rear window went down - I thought maybe someone slipped me a mickey somewhere... I've had the truck 2 yrs. I want my cruise control working! I know how hard it is to identify elec probs. I owned a bonneville from electrical hell once!
Back to the codes here. I am most concerned about the cylinder code.
Thanks in advance for any direction. Short on money here so between you all and my Haynes I will attempt my own diagnostics/repair. No, I have not changed plugs/wires but did buy them today on a hunch.
~merry holidays, nancy


New Member
April 30, 2009
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City, State
Mission, Texas in the Rio Grande Valley
Year, Model & Trim Level
'94 Navajo LX 4x4
code 538 is exactly as dogfriend said. when you get the code 10 you are supposed to gun the engine then release it immediatley, this is to measure the WOT response so thats why the code reads inssuficient RPM


Explorer Addict
February 19, 2008
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City, State
Flowery Branch , Georgia, 1994 sport 2wd auto
Year, Model & Trim Level
2005 colorado 2wd 5spd
umm you noticed that your responding to a old thread ...look at the date ;)