EEC-IV basics

[Mad Tiki]

Regarding your issue with the fuel pump relay; it could very well be more of a problem in the plug itself. I have seen the wiring insulation deteriorate and also the wire strands breaking causing the resistance to increase. Have you tried replacing the electrical connector to the relay?

S-659​

Electrical Connector​

POP: D​

Per Car: 1​

Thanks for the suggestion. I have been through the fiel system as far as new pumps. And new sending unit. I also removed and re sealed the tank. I noticed that the factory wires at the plug are a bit worn. I was considering just running all new wires for the injection system from the relay.
While swapping to the more common configuration relay at the same time.

 

[Rod Beauvex]

I have troubling questions.

Did the 351 and 460 ever get CFI, or did they go from VV carbs directly to mpfi?

Does the CFI run its two injection in perfect sync, or are they independently fired?

On the batch fire motors, how many batches are there? 2 or 3 for sixes, 2, 3, or 4 for V8s?

If the answer is 2 for both, than is there any actual difference between between the CFI ECUs and the batch fire ones, other than the fuel/timing tables on the ROMs and the amount of injectors on the output lines?

Will a 5.0 CFI run a 300 six with the appropriate sensors, distributor, and intake, like Clifford with a 2BBL adaptor? If yes, then will the Canadian Essex 3.8's CFI system run a 240 with said setup, seeing as there is less than 1% difference in them, displacement-wise?

Is the Essex 3.9 V6 setup speed density?

 

[Rmoore45]

MechRick,

Thank you for posting all of this information! These older injection systems are simple and reliable but can be difficult to diagnose at times.