hey fellas I could use some help,i have a 1988 w150 5.2FI the motor locked up so I put in the 5.9FI all but im running the stock 5.2 sensors and computer the truck starts revs great but after it runs for a sec it idles up and down then driving it has no power ,it bogs down and when it warms up it cranks for a long time before it starts

it has new,
fuel pump
coil
pick up coil
plugs wires cap and rotor button
TPS
oxygen sensor
and I tried another computer from junk yard with same results

 

Try getting a 5.9 computer. The 5.2 PCM will run leaner than the 5.9.

 

ok I was woundering about that, do you know if a 1989 5.9 ecu would have the same plug ins?....thanks

 

I honestly don't see why. From what I know, I don't think a ton changed between 88 and 91. You can always just go to the jy and see.