Intermittant stalling associated with erratic Fuel pump relay activity. Sounds like Morse code. Tried swapping out FP relay and PCM relay during failure with no improvement. Normally with KOEO, fuel pump will only run appx 1 second when key is turned on, unless cranking or running, but this erattic relay condition can last for minutes with KOEO! Tried jiggling Ign switch thinking a possible intermittant contact issue may be causing this failure. Bypassed direct bat + to fuse #14 output circut direct to fuel pump and pump would then run normally, but still erratic FP relay condition continued. When in failure mode, voltege at fuel pump was varying as expected from 0 - 12 volts in sync with erratic FP relay activity. Charging / battery system tests all normal. Checked PCM grounds, Battery connections and all accessable related grounds, which all appeared clean and tight. Remoced PCM and inspected connector pins = OK. Recently had MAF and throttle plate cleaned by others. System does not have the FRP (fuel rail pressure sensor). MIL on when arrived at shop. Codes found PO231 , P0500, P1703. Cleared codes and none re-appeared after recent failre event except the P1703 (brake switch). NOTE: may be of interest. Code P1703 brake input failure...scan tool test revealed PCM not recognising Brake switch on/off, though brake lamps work, as does the trans interlock solenoid. The P0500 VSS code was in the historical codes but vehicle speed reading on scan tool is normal when driving. Checked its connector = OK. Courious if anyone has ever expeirenced this weird FP relay situation and Would appreciate any pin-pointing suggestions at this point before back-probing values at PCM, hopefully in a failure mode (which unfortunately is not too often,anywhere between 5 - 112 miles lately...) one last note: KOEO self test says "no communication" thouhgt you can hear it cycling threw tests..? KOER performs normally except always gives a P1000 (incomplete test message)

FIX posted 5/31/2009

Brian from Washington

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