I have been helping my daughter with her van. She had an issue where a relay or something went bad and the fuel pumps were staying on without the key in the ignition, draining the battery. I believe I have fixed this issue and now the pumps turn on when the key is on and off when the key is off. But now the vehicle cranks but wont start....

I have confirmed spark. I have confirmed fuel pressure and fuel flow up to the injectors fuel rail, but the injectors have no electric pulse going to them. I have used a noid light and a multimeter and it appears they get 12v+ signal but no ground from the ECM.

I'm thinking about getting a new ECM at this point, but the current one is an AC Delco remanufactured unit and not original. It has been impossible to get any ECM seller to guarantee fitment without the original ford part number.

Any ideas on how to confirm the ECM is the issue and secondarily, how to obtain the correct replacement ECM?

 

Since power is available to the injectors anytime the key is on, the `ECM does provide the ground to activate the injectors.
Like any other check, you could connect a test light probe to any injector ground wire and crank the starter . You should see the test light come on when the ground is sent from the ECM,,, IF it is working..It is a short pulse and the light blinks if the ground is getting there. The test light clip gets connected to battery positive.

 

Thanks for the response Hanky!

I used a noid light tester as well and they do not light up when cranking the starter. I tested this at the injector plugs and the ECM's 60 pin output using a wiring diagram I obtained from Shop Key Pro, which is supposed to be specific to my VIN number. However, I have noticed that some wire colors do not match what it says they will be on the wiring diagram.

I am wondering what items connect to the ECM to tell it when to send ground to the injectors, on this van specifically. When does it know when to pulse which injectors and what items could prompt the ECM to not pulse the injectors?

 

Got a new ECM and now when I turn the key to the on position, you can hear the fuel pump kick on for only a couple of seconds instead of running non-stop. The noid light tester confirms signal is now reaching the injectors, unfortunately, it still cranks but wont start. Ahhh!

I checked for spark with a spark plug grounded and there is now no spark reaching the spark plug. I'm not sure if I should start testing backwards for spark or plug the old ecm and see if I get spark.

 

It certainly won't hurt to see what you get.

 

Okay so after swapping the ECM's back and forth and taking a closer look at things, it turns out there is no spark with the original ECM either. There definitely 100% was spark on the old ECM after the vehicle stopped running, and the new ECM definitely fixes the fuel issue.

So basically the fuel problem is fixed but now there's a new one with the ignition.

I found a fusible link that is bad between the coil, distributor, and ECM. The diagram shows the fuse slightly different from reality. In reality the fuse is where my arrow is in the pic.

I'm concerned that whatever caused this fuse to blow will burn up the ECM if I simply replace it with another fuse. Should I just replace it anyways and see what happens? It is a inline fusible link (popular in the 80's I guess) and it is located right next to the engine a few inches down from the spark plugs.

 

Okay turns out this is a resistor, not a fuse. I'm not sure if it's bad or not but it's probably fine.

What is the easiest way to verify the ignition coil is sending spark to the distributor?

 

This is what I would do.
Take the output wire from the coil that goes to the dist and place it about 3/8 ths of an inch from any ground, engine block is fine.
Crank the engine over with the starter motor and you should see spark coming out of that wire trying to get to ground. That is a quick way to see if you have any spark coming out of the coil. Either you will have spark or no.

What did you see ?

 

Okay so I tried that today and I am not getting any spark from the coil to engine block. I even bought an inline spark plug tester and still couldn't get anything when running it inline to the distributor or to the engine block. So I replaced the ignition coil tonight thinking, why not, even if it's not the issue, it wouldn't hurt to have a new one in there and rule that out. But I got the same results. What can I try now?

 

Any ideas now? I hear the ignition control module (mounted to the distributor) and the distributor pickup coils on these units are a common place for failure and cause no spark conditions. How hard is it to redo the timing if I replace the entire distributor? They're cheap on rockauto. I have access to a timing light but I've only used one once and don't really remember the process.