Cracked block in my 24v 98.5, found a good deal on a 2002. Installed easily, but now has no power or acceleration (will start ok). Tachometer works for a few seconds, then drops to zero and the check engine light comes on. Surges horribly as well. I left the crank sensor connector loose (since the 02 doesn't have one), installed an 02 computer. I'm showing codes for a camshaft sensor (which I replaced) and 1693. I was told to replace the map sensor to a 2002 one and that should fix the problem. Just wondering if anyone else has done this kind of changeover and what else I need to do.

 

Do you currently have the map sensor unplugged? Unplugging the sensor on a stock truck will result in very low power like you describe.

 

Map sensor was plugged in but it was the 99 one, I haven't tried with the 02 map sensor yet.