02 missing and gutless for power (codes included)

sleazy rider

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Old beastie decided it hadn't gotten enough love apparently. Went to golf yesterday morning running fine with plenty of fun in the right foot pedal, left the course and the engine started stuttering under load and a CEL. Got home, checked codes and had a bunch. P0031, P0051. P0306, P0136 and P1598. Misses on both banks, bank 1&2 upper O2 sensors and a/c pressure level. Sounds like the down pipe of the exhaust has a leak now too.

Disconnected the battery, did the terminal tie thing first. While it was disconnected, I pulled the connectors on the PCM to check for corrosion - clean and shiny. Cleared all the codes when the battery was reconnected and hasn't reset any, but the stuttering still exists with a noticeable lack of power.

Oil is clean and clear.

Any suggestions where to start?
 

DadOSix

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Old beastie decided it hadn't gotten enough love apparently. Went to golf yesterday morning running fine with plenty of fun in the right foot pedal, left the course and the engine started stuttering under load and a CEL. Got home, checked codes and had a bunch. P0031, P0051. P0306, P0136 and P1598. Misses on both banks, bank 1&2 upper O2 sensors and a/c pressure level. Sounds like the down pipe of the exhaust has a leak now too.

Disconnected the battery, did the terminal tie thing first. While it was disconnected, I pulled the connectors on the PCM to check for corrosion - clean and shiny. Cleared all the codes when the battery was reconnected and hasn't reset any, but the stuttering still exists with a noticeable lack of power.

Oil is clean and clear.

Any suggestions where to start?
interesting set of codes.

I would be thinking - maybe - low battery voltage.

Like, how is your batt voltage - engine off. Are you +12.5 volts or so?
Running- are we charging? 13.8 or thereabouts

In ref to the o2 codes - grounded or bad wiring?

Without looking at the wiring diagram, the inclusion of a/c data leads me to the possibility of a bad ground. Would need to look at the diagram and see if anything in common here with ac and o2 sensors.

Just for fun, I’d try a ground directly from the batt to the engine block to see if anything changes, particularly if the system voltage is in correct range.

If those voltages above and not where they should be, look at batt / terminals / etc 1st.
 

The gov

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Just finished dealing with a similar situation, ground on the engine to body was what I thought was the culprit, turned out that evil green corrosion at the bottom of the fuse box, used some dielectric spray penetrating fluid after a light cleaning, seems to have worked, buddy hasn't called me so I assume it's working. hopefully it will be a easy fix for you, remember these old girls are getting long in the tooth and eventually wiring harness and connector points do need a little TLC.
 

sleazy rider

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I'll be on this just as soon as the monsoons stop. lol We needed the rain, but holy shamoley, Batdude! Had puddles in the backyard last night and we're on a sandy loam that just ***** up water.
 

sleazy rider

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Hmph! Rain quit, heat went up and the beastie now starts and runs like normal. Something electrical got wet is my opinion. Could have been when I cleaned up after all the last work too. Strange.

Voltages on the battery are good non-running and charging.
 

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