Running like crap, P1260

[nghtshd88]

So I literally shut my LS off and locked it. Ran into a store and came out. Upon starting it was running like shit, almost stalling, hard to even keep it going . Gave it some gas and it within 2 mins it was running smooth and the roughness was gone. Thought it was maybe fuel related because it felt like I had lost half my coils lol.

Drive away fine and park again shut it off try to restart and now theft is enabled p1260. I didnt even remove the key though.

How are these two related? I have new coils plugs and run 93octane, new fuel filter. Has been running beautiful until now. I know when coil #4 is bad it goes into failsafe mode.

Gen II 3.9

 

[RigsLS]

Possible loss of power or ground to PCM.

Did an audio shop recently install a remote starter by change?
Check your battery and connections.

For now you'll have to clear the Keep Alive Memory by means of disconnecting the battery terminal connections. >30min.

When it does it again, obverse the PATS light.

 

[nghtshd88]

It is 100% stock no audio yet. My battery is fairly new as well, connections were good. PATS light was blinking. I opened and shut all doors and got P1260 fixed and got it to start. P1260 has happened to me twice before. Not sure if it can be key related but this time it was stalling out.

I did have one ground off behind the intake manifold but secured that when I did the plumbing.

Oh somehow my trip odometer reset itself as well last night. Odd.

 

[joegr]

...Oh somehow my trip odometer reset itself as well last night. Odd.

This does seem to point to a power loss problem. Besides the battery cables and major grounds, check the fuse/relay box in the trunk for corrosion or loose contacts. Also check the fuse box under the hood. Some have had issues with corrosion at the socket for the PCM relay.

 

[RigsLS]

... and with the milder weather these days them little electrical gremlins and their corrosion cousins come out to play.

Also, do try and remove all crap with barcode strips on them from your key chain, try just the key and the associated FOB. These can interfere with the PATS but in this cause not so likely as it's already a start condition then stalls out due to loss of power or ground.

Like Joe says, have a look at all the connections, cables, fuses and such.
Find the fuse for the PCM and re-seat it. Check for dampness and corrosion all over.

GLWR
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