Having trouble starting. Have checked and redone splices in wiring harness - power to ASD & fuel pump relays and multiple ground splices. When key is on if check engine light comes on, fuel pump runs and truck will start. But unreliable. Most of the time the check engine light does not come on, fuel pump does not run and truck will crank but not start. When it does start, it will run well and drives OK until I turn off. If I try to restart it immediately, it will start but if I wait a few minutes, it won't. Suspect the PCM but not sure. Someone mentioned ECM replacement. Is ECM the same as PCM (basically the computer module)?? Thanks for your help. I have been at this for nearly 2 weeks and running out of ideas.

 

Welcome to the site. I will move this thread to the first generation Dakota section,
FF

 

Have you pressure tested the fuel lines? Could just be that the fuel pump is going out.

 

Replaced fuel filter and fuel pump before I found out it was an electrical problem. When engine check light is on and fuel pump runs, truck starts easily. Problem is no check engine light and fuel pump and ASD relays do not pickup with key on. Thanks, any other ideas?

 

So your check engine light stays on all the time when the truck runs? And if its off the asd box gets no power?

 

Thanks for your input but NO the check engine light does not stay on when truck is running. When key is first turned on, the check engine light is supposed to come on. My problem is that it does not come on and ASD and fuel pump relays do not pick up. Once in a while it does come on and when it does, everything works as it should. I don't know how the light is related to the relays but if the light does not come on when key is turned on then fuel pump does not run and even though truck will crank, it will not start.

 

You have a wire problem somehow. The relays get activated from the ignition switch. So the switch or wires from the switch to the relays could be bad. Next the ASD relay turns on the computer. The computer is not getting power and causing your check engine light not to come on. Again the power splice just under the relay box is the typical problem.

 

Ok...thats far more clear. I would agree with crazy. Its gotta be a wiring issue if its intermittant and the relays arent working.

 

crazy 4X4 - thanks - I will look for additional splices - I have already redone several including the 3 red wires from the relays and three sets of ground splices. The 12v is getting to the relay coils but I think the return or ground is through the PCM somehow. (?) I checked for 12v to the PCM on a dark blue wire about #16 or #14 and I think it is the same circuit that takes 12v to the relays so when relays pickup 12v is sent to fuel pump. Sometimes the relays chatter and I think the EGR solenoid chatters at the same time as I felt it when the chattering is going on. I have a wiring diagram that I got on AutoZone web but the one for '93 Dakota 5.2L isn't accurate as it shows fuses in circuit to relay coils and I know they don't exist. Hate to be so wordy but I appreciate hints and all the help. I will get into the wiring harness further. Could the PCM be bad? And do you know how to read the terminal numbers on the plug. The diagram has pin numbers but none on PCM plug??? Thanks again. I have driven this truck (4X4) for many years with no such problems and loved it. I lost the positraction rear end once and had it replaced but I think I tore it up when in the mtns. in deep snow.

 

If you got all the splices then check the wires. You can find the wiring diagrams in the FAQ in this section. Check to see if the relays are working. Have someone turn on the key when you wait to see if you hear them clicking. You can even take off the covers to and see them move. Yes the PCM plug has numbers on them. You can also look in the FAQ for the service manual that has a diagram of the PCM plug.