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Topic: computer codes (Read 2654 times) previous topic - next topic

computer codes

I had my check engien light turn on checked the code and it was a 98 which when cross referenced to the mustang mass air computer it says " Hard fault present "

Anyone know what this means?

Re: computer codes

Reply #1
My list says:

98  (R) Did not pass KOEO yet (Get 11 in KOEO first)

Shotimes, Mustangworks and likely others say:

Hard fault present. The PCM is running in FMEM (Failure Effects Management Mode), so something is royally screwed up that the KOEO test should have told you about. Rerun KOEO and fix whatever you find there
Death awaits you all with nasty, big, pointy teeth.

1988 5.0 Bird, mostly stock, partly not, now gone to T-Bird heaven.
1990 Volvo 740GL. 114 tire-shredding horsies, baby!

Re: computer codes

Reply #2
I am also getting a code 66 from the computer when I amrunning the KOER test.

Re: computer codes

Reply #3
66  Vane Air Flow (VAF) or Mass Air Flow (MAF) signal low - VAF MAF

Is the MAF plugged in properly? Any wires broken?
Death awaits you all with nasty, big, pointy teeth.

1988 5.0 Bird, mostly stock, partly not, now gone to T-Bird heaven.
1990 Volvo 740GL. 114 tire-shredding horsies, baby!

Re: computer codes

Reply #4
I wired everything the way I was told to for the mass air conversion.

I spliced the power and ground for the mass air to the power off the computer. Could that be the problem.

Also when I plug the mass air meter the engine light turns off and the car starts to jurk bad. It runs fine whent he sensor is unpluged though.

 

Re: computer codes

Reply #5
had 98 on a 3.8, they hooked up the wrong connector to the water temp sensor for the computer