DODGE RAM FORUM banner

1 - 5 of 5 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter #1
Well I’m out of ideas..
1989 Dodge W100 318/4speed TBI
I swapped the original 318 with a 318 I rebuilt. Truck ran perfect before the swap, now I’m not getting any spark.

Im not getting power to the positive side of the coil, fuel pump. Check engine light also doesn’t work anymore.

- I checked/ replaced the ASD relay; constant 12v to red wire, 12v to blue/white wire with ignition on, nothing to green wire
- Tested/ replaced coil 2.4 primary, 9500 secondary
- Traced coil wires back to ASD/ ECM
- Repaired/ replaced any bad spot on left side wire harness
- Replaced Hall effect; 8v to pin 2 and 1.25 to pin 3
- Cap/rotor/wires all new
- Cleaned all connectors from sensors to ECM
- All grounds on left rear of engine good, new ground wire from battery to block, battery to body
- Replaced ECM

The only sensor I did not hook back up yet is the 02 sensor because I put headers on and have not sent to exhaust shop yet.

Any ideas would be greatly appreciated.
 

·
Registered
Joined
·
1,006 Posts
The asd relay should come on as soon as you turn the key to on, It doesn't stay on only a short period. It supplies 12+ to the coil, If you are not seeing the check engine light (key on) i suspect there is an issue with the pcm(or wiring) or no power going to it.
 

·
Registered
Joined
·
7 Posts
Make sure you have power (+12vdc ) at the ignition switch , it is supplied from a fusible link ,( big problem area for all odd electrical issues on gen 1 Rams ) , when you turn on the ignition it sends power to the ECM among several other components , most +12vdc come's through fusible links.


Dark grn wire supplies the power control module on a 91 , 89 may be different , mine lists 90 &91 on the wiring diagram. Drkgrn / blk supplies both the fuel pump and the coil on my 91 , blk/Yel is path to grd for the coil triggered through the ECM
 

·
Registered
Joined
·
2 Posts
Discussion Starter #4
Thanks. Well I replaced the left side wireing harness and got spark back. Not sure what caused the issue with the old harness.
 
1 - 5 of 5 Posts
Top