I've replaced everything in my 1991 Starter system. Going backwards, Starter, verified continuity of hot & gnd wires, Solenoid, Battery, Elect.Control Mod. and NO GO. There is a relay I've not done yet, but some intermediate testing is showing other problems.

Being concerned the battery(although brand new) was a fault I took it to be tested, its Good. The Starter I worried was problem, had it tested and it works. Doing the old Cross the Contacts on the Solenoid to hear the starter turn over FAILED. So regardless if the EFI Mod and Relay are any good, crossing the Solenoid should Still Work, but it doesn't.

What is the electronics involved here anyways? I pulled the started and tried to test it myself, and using 12 volts from the battery AND charger, neither would turn it over. Yet at Advanced Auto their machine cranked it like a champ, worked fine. What happens in the Solenoid? Isn't it just a relay switch more or less?

WHY does the starter turn at the Auto Store and not using my 12 volts?

 

is the starter solinoid fender mounted? if it is put a large screwdriver between the two large terminals, might spark a bit but should crank, if it does put the ignition on and try again with the screwdriver, if engine runs there might be bad wiring or a fuse (or starter relays that provides the ignition switch)

 

https://www.f150online.com/forums/pr...ing-again.html

 

Thanks Strange..will look at the cables. Quite possibly the problem. Curious, any idea why hooking a 12volt charger directly the the starter wouldn't turn it? Put it on 50amps. Think it takes the 600amps of a battery?

 

Starters draw something on the order of 175-200 amps but only for a few seconds

 

Well I undid the ground cable at the battery end, and also the short one that connects onto the frame forward of the battery, cleaned them VERY good, spraying contact cleaner on them also, and put them back. It turned over first time. Culprit: BAD Wire Ends/Contacts

 

Trucks still not starting, but it was late and dark, and I didn't feel like looking but sounded like it wasn't getting gas. Probably empty, or stolen. Will find out tomorrow.

 

So yeah, she's Cranking like a CHAMP now. Only, she went down about 10 weeks ago and hasn't ran since, and now cranking is all she'll do. I'm sure the fuel was low then, and have been concerned in the past someone thinks they need my gas more than I do where the truck sits is kinda quick access for late night shoppers. I put maybe 3 gallons in, but no change. What's the deal with EFI systems that run low on fuel? I've heard bad stuff in the past but never knew for sure. Will she prime herself if I keep cranking? I'm not even sure that's the problem, but before the starter went out all else was fine.

 

If it's been sitting awhile then change the fuel filter.

Then check the fuel pressure regulator by pulling the vacuum line off and see if there is gasoline present in the line. If the line is dry, the regulator is probably OK.

Then turn the ignition to "on" but do not crank it. Listen to see if you can hear the fuel pump running. Depress the stem of the Schrader valve on the fuel rail and see if there is fuel present.

 

Ok, to back step, just ta let ya know, it wouldn't even turn over again, so this time trimmed the bad cables back, cleaned them very well. Cranks great. Bad Grounds can be a Bugger!
..
Now, replaced the fuel filter, kinda skipped the Press.Reg. for a moment because it was easier to listen for the pump first. I hear a click, but if I recall right didn't I used to hear it sorta run for a couple seconds??? If so, I'm not hearing that now, just that click.

 

The click is the fuel pump relay. The pump is supposed to run for about 2 seconds to prime the system.

 

That's what I was thinking. I've not driven it for sometime, it's been my wifes auto for awhile. Well, I'm not hearing that, so either some electrical component not allowing power to get to the pump, OR the pump. It just keeps getting better.

 

Actually there are two relays, the PCM relay which turns on the processor and the fuel pump relay which is turned on by an output from the processor. You need to check them both.

 

Ok, bought a Fuel Pump Relay, based on the auto stores clerk choice. He sold me a 5 pin but I have a 4pin. I'm guess that 5th pin is fine, it'll just not be used? Is that the case? Because looking online Adv.Auto doesn't have my 4pin, every picture of every one has 5.

Now the PCM Relay, can you steer me towards it? I'm digging all over the Web and can't see anything saying which it is. And of course the Auto store guy was clueless on that as well.

******** UPDATE: See Below post...shes R U N N I N G ! ! ! *****************

 

Well, I finally figured out that the EEC is the same as the PCM relay, just different names. And I know where it's at.

Or at least that's what I just read.

* * * * $ $ $ % % % ^ ^ ^ UPDATE * * * UPDATE * * * * * UPDATE ! ! ! ! * * * * * * * * *
It's RUNNING!! I was impatient and had to try the Relay. Plugged it into the Fuel Pump, turned the key, no change.
Figured, What the Heck. Put the old one back in, and swapped the New Relay with the old EEC Relay, turned the Key and WA'LA! I hear the fuel pump come on. Before I cranked it had to turn it off/on so i could hear it again. Like MUSIC!! Cranked it and in 5 Seconds the truck was running. LIttle Sputtering, but RUNNING!!

Now to figure out where the other end of that lose hose goes!! hahaha..I'll find it.

You FIXED it S.RANGER!! THANKS!!!