89 blazer

[sig99]

i have an 89 blazer in which the fuel pump relay wire from the ecu was shorted out. the balzer is a 2.8 with m/t and a digital dasn. i replaced the ecu with one that was in the junk yard but it had an auto with analog dash. it has had a tune up within 1 year ie cap rotor plugs and wires. but the vehicle will only do 50-60 going down hill with the wind. it ran fine b4 the ecu swap. can anyone help

[GM-Tech]

I think you need to make sure you have the proper ECM and PROM before attempting any other diagnosis.