Thanks kr98664

Last 6 digets of VIN for my 2001 S-type is ---- L87347
Useful ... Although I already purchases a used throttle body for S-type 3.0L, of same vin range.
Thanks to everyone to all their help and concern
Especially NBcat and you.

Thoroughly confused as what to do next.....
Perhaps PCM is trash... or missing a file.. seems unlikely, but possible.
Car was driving perfect before all this.
now driveable at under 2000 rpms.
"limp mode" I guess. Always re-starts immediately after stall above 1900 rpms.
Engine sounds fine.

 

PCM is about the last suspect but you could check it's not wet or been wet.

 

+1 on that. I'll readily admit I'm stumped, too. A couple of random suggestions, of unknown usefulness:

1) Do you know any of the history of the donor throttle body? For all we know, the donor car had the same P1586 fault. You'd have to be 100% positive it didn't before conclusively ruling out the donor part. If purchased from a wrecking yard, don't necessarily trust the seller's word. He has a financial incentive to say your current problem isn't caused by the part sold to you, so take any statement with a grain of salt.

2) The wiring fault you found: IIRC, you found one wire with bad continuity from end to end. Is the replacement wire now completely isolated from the existing suspect wire? What I'm getting as is perhaps there's more damage in the harness. You obviously checked each wire end to end. Did you also check each wire to ground? This could be caused by a bare spot touching a metal bracket, for example. Or what if you had two (or more) wires rubbing together? This is very time-consuming to rule out, but I'd say you've reached that stage. Wires touching each other would still show good continuity end to end and appear good, but still misbehave in a live circuit. Considering you already found some damage, and yet the problem still continues, there's a good likelihood of further undiscovered damage.

 

In response to your question...
Testing problem is that wires become included with all transmission and engine wires into cabling that disappears behind engine.. impossible to easily determine.
I tested end connector to end connector... TB connector to ECM connector
zero resistance and full continuity on all wires..except white. White wire tested with some resistance.

Primarily... This "non communication issue" & codes.. only began immediately after mobile-mechanic technician hooked up his Snap-On computer to resolve a sensor conflict... Apparently something he did..caused SCP communication error and TB communication error.. car will not accelerate more than 1600 rpms without shutting down engine.

Still unresolved.. my S jag 3.0 is parked, while I deal with problems in my Jaguar VandenPlas.

Please reply when you can..
Bradley

2) The wiring fault you found: IIRC, you found one wire with bad continuity from end to end. Is the replacement wire now completely isolated from the existing suspect wire? What I'm getting as is perhaps there's more damage in the harness. You obviously checked each wire end to end. Did you also check each wire to ground? This could be caused by a bare spot touching a metal bracket, for example. Or what if you had two (or more) wires rubbing together? This is very time-consuming to rule out, but I'd say you've reached that stage. Wires touching each other would still show good continuity end to end and appear good, but still misbehave in a live circuit. Considering you already found some damage, and yet the problem still continues, there's a good likelihood of further undiscovered damage.