wiring problem with 4 to 8 cyl conversion

87PonyBoyGT

New Member
Sep 5, 2003
24
0
0
north jersey
well i guess my first mistake was doing the conversion lol any way the motor is from a 91 mustang and the body is a 89 4 cyl. so the installation was going good mechanically till i went to go start her up all i got was cranking. so i went to check for fuel and the lines were dry. so i go to the fuel pump relay and my problems began:bang: . im getting 5 volts from the ground side signal and 1 volt from the ignitions signal side. so i jus jump the relay to get fuel pressure and still crank with no start. so i go to the eec power relay and i have the the same problem as the fuel pump relay, there 5 volts just sitting there on the signal wire so i go checking everything else and i have 5 volts sitting at the injectors. i have no idea whats going on:shrug: any body with any input or wiring diagrams would be plenty helpful
 
old_blue said:
is the computer out of the 91??? all the wiring for the motor out of the 91??? maf i assume??

yea all the wiring and the comp is out of the 91. another thing is i have 2 unplugged connectors that im not sure of. one from the motor harness( a cicular connector next to a green one) and another similar circlar connector near the booster come from the cars harness/ fuse block. im not sure what they are for but they are there unconected.
 
If you used the 91 engine hanress with the 89 dash hanress that is you problem. The 91 engine harness has one plug( redish brown looking) by the booster, and the 89 dash hanress will have two(blk & gry). You can do some re-wiring with the hanresses, or swap an 89 engine harness.