Engine running issue

[junglejuice]

Hi guys I had a guy here today who requires some help regarding an issue he has with his 96 Xj, when it is cold it runs fine but once upto temp it will feel severely restricted over about 2000rpm, below this it is fine.
He has replaced both CPS's, the TPS, the entire distributor with new cap, leads, plugs etc, the coolant sensor was also replaced along with a new coil but no change.
So today we replaced the complete throttle body, no change, the cap, leads coil etc swapped out with one from a running car, no change.
We also swapped the Cam sensor, no change.
We swapped the PCM, no change.
We swapped the manifold temp sensor, no change.
We disconnected both O2 sensors, no change.
A brand new fuel pump was fitted and it appears to have plenty of fuel pressure but I don't have a pressure guage to verify the pressure is correct.
The battery is almost new and larger then stock.

Nothing we did made any difference, all parts were removed from a running car, the engine sounds willing, and pulls strong till it feels like the handbrake is pulled on, it doesn't feel like it would if it was a typical ignition break down issue, it is like the PCM is regarding the power.
The catalyltic convertor was checked for blockage but appeared to be clear.
Can anybody suggest anything that I have overlooked?

I,d like to try to help this bloke out as he has just bought this car, I suspect the PO sold it due to this issue and he is new to Jeeps from Toyotas.....

Any constructive comments will be greatly appreciated......

[Roler]

when u say restricted over 2000 rpm, does it go beyond that or ur not getting up to higher revs?

[junglejuice]

No it is like a rev limiter, that would have been a good way to describe it.....

[The Smiths]

Originally Posted by junglejuice

We disconnected both O2 sensors, no change.
......

petrols are not my thing - but would have thought doing the above should have made a difference (for the worse), unless they were fubar and not working??

Sounds like a limp mode of some sort

[kjparker]

any codes?

[anthonygubbin]

Have you got another OBD2 ECU to try JJ?

Regards A

[COFFMAN]

Check Exhaust cat convertor ...................