Computer Throwing Codes

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Black91SHO

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Alright, I just pulled codes off my '91 SHO. I wanted to see if anyone has gotten them before and how you fixed them. And heck, I don't even know what some of them mean even after looking them up in the manual.

KOEO Codes
14 - C - Ignition profile pickup (PIP) failure (not sure what this means, but I'm guessing it's the throttle position sensor)

45 - C - DIS coil pack circuit failure (is this the DIS module, or the coil pack itself, or just the circuit they're on? Maybe this is causing my idle problem.)

91 - C - HEGO (HO2S) sensor voltage out of range / always lean (cased by cats being shelled out?)

KOER Codes
77 - Operator Error during Dynamic Response Test / wide open throttle not sensed (not important)

74 - Brake on/off (BOO) switch failure; not actuated (my brake switch works fine...it's new)

52 - POPS (PSP) circuit out of range (no idea what this means)

Cats Shelled Recently
They were broken, so I shelled them for the time being. Won't that make it run lean? Will the computer correct that problem eventually?

SEFI
Are our car's SEFI (meaning the injectors spray one at a time in sequence)? I was under the impression they were, but when I tried to do the cylinder combustion test--I think that's what it's called--the test wouldn't start. Maybe the test didn't start because I didn't press the gas gently enough after the KOER test. Has anyone done this test?

Thanks.
 
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rubydist

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14 = PIP circuit failure (crank sensor)
45 = coil 1 failure
91 = front bank oxy sensor not switching
77 = brief WOT not sensed during test (operator error)
74 = BOO no change during test (usually operator error)
52 = power steering switch did not change during test (usually operator error)

If the stored codes are current and not from the distant past, then I would be looking to change the crank sensor, and the coil as well as the front oxy sensor. However, the coil code is just as likely to actually be the DIS in my experience, so you may need to change that too or instead.

During the koer test, the pcm expects to see a brief WOT, a brief step on the brake pedal, and a turn of the steering wheel to the left and right, at the correct time of the test. If it does not "see" these, it reports the 52, 74, and 77 codes. So, they are generally not important.
 

Black91SHO

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Thanks.

The crank sensor was changed not long ago. That's probably a really old code. I should clear the codes.

The front O2 sensor may well be bad. But you don't think that code could be due to the cats just recently being shelled out?

What do you mean "coil 1"? You mean the entire coil pack?

I just swapped coil packs, so maybe that's an old code, too.

The DIS hasn't been changed in about 3 years. I suppose that could be an issue. I'll clear the codes and see what comes up.

Thanks again.

Sent from my SM-G920T using Tapatalk
 

AREA 91

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Clear the codes and take it for a drive.
Check the codes again.
 
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