Loss of Power

92 XJ AW4 210,000 miles.
Engine power does not increase above about 2250 rpm. On the slightest incline I have to floor it, but it does no good. No increase in acceleration with throttle position or rpm. Its as gutless at 4,000 rpm as it was at 2000 rpm. It simply wont accelerate.

I did a compression test. Engine warm (not hot), throttle held open, 10 strokes.

1 152
2 135, 146, 148
3 157
4 146
5 152
6 158

After testing all 6 cylinders I went back and tested #2 two more times and got the higer readings. Motor is good internally based on compression test.

I have read dozen or so similar threads. Suggestions were TPS, Fuel Pump, Injectors, Fuel Filter, 02 sensor, and clogged Cat. All but one thread ended with no solution found. The one that had a fix said it was a clogged Cat.

I am going to do a normal tune up tomorrow (plugs, wires, cap, rotor) since its been about 80Kmi and I will toss in an 02 sensor for good measure since its the original unit.

Anyone who has seen this problem and fixed it pleas post up.
I would also like to know how test injectors and TPS.

Thanks

John

it sound like the cat in no good my dads truck did the same thing it was the cat

If it's gutless but still runs smooth uphill, and runs fine downhill, it's probably the cat. Most of the other causes would usually cause it to stumble a bit. Not as much exhaust needs to flow through the cat going downhill...

Jim

The symptoms certainly sound like a plugged cat. Unbolt the exhaust at the manifold, clamp it out of the way really good and take it for a test drive. Preferably not at 2am through the neighborhood. :}

And clogged cat can be tested for with a vacuum gage. It will show steadily declining vacuum.

It was a clogged catalytic converter. I just had a new one put on and it fixed all the problems. Runs great with good power all the way up to 5000 now.

Thanks for all the advice.

John