Hi Ya'll! I'm new to the forum and to working on trucks.

I have a 1985 F-250 V8 5.0 L EFI (Type N) Duel tank, Manuel 5 speed transmission, with 4WD. I have problems with not having her start reliably. The issue started with not starting after the truck is hot. It has now progressed into just not starting at all. On the rare occasions that she does start, it runs and idols rough. Additionally, the power is low.

When the FSM tells you to use a 'VOM' to measure ohms or volts, its talking about a multimeter, is that correct?

The Haynes manual says that the issue lies in my electrical or fuel delivery system. It may be some of both and frankly I'm overwhelmed with the problem(s) because I'm new to working on anything other than a motorcycle. I need to be able to use it this weekend too.

There is no problem with the engine cranking & the voltage at the battery is a little over 12 Volts.

I sprayed starter fluid in the air intake and the engine did NOT fire even for a couple of seconds. That particular issue indicates to a couple of people more knowledgeable than myself that it could be a bad coil. They said that after it gets hot it could be unable to produce spark any longer. However, when I pull the plug that goes to the distributor cap I get spark even when its hot (about 105 ° F).

While I had her propped up I started the engine and allowed it to idle for over 10 minutes. Then she sputtered out and died. It sounded like an engine does when it runs out of gas. Tried to start it again but all I got was cranking. So I decided to start troubleshooting the fuel system.

I found out that my truck is one of the lucky few EFIs that didn't come with a fuel pressure diagnostic valve on the fuel rail. But I decided to start by troubleshooting the high pressure fuel pump on the rail.

The first thing the FSM says to do is disconnect the connector from the body wiring harness and measure the resistance across the body connector. I did so and got a value of about 8.5 ohms. Because it was higher than 5 the manual said to verify ground on each wire. They both ground without issue. (I get the beep sound from my meter.)

Does that mean the 8.5 resistance isn't a problem?

I then checked for continuity between the pump terminals and it has continuity as well. The next step was to see if I'm getting 12V at the pump for 1 second when the key is first turned on. The problem is that I'm not sure of the readings...

If the multimeter is set to auto find the range (starts at mV and then scans to see if it goes up to volts...) I think I see 12 V. I'm not sure because it flickers on and off so quickly that I don't know if its showing 12 mV or 12 V. If I force the range to only show Volts I get what appears to be a brief change but nothing that lasts for at least a second.

So, does that mean the voltage is within specification or not? If not the manual helpfully tells me to: 'check the electrical circuit and repair as required'. In the table of contents, it shows that I'd need the engine/emissions diagnosis manual to troubleshoot that kind of issue (which I don't have).

Am I even on the right path or should I be looking somewhere else?

 

VOM= volt/ohm meter, correct. OK, you provided fuel and it still wont start, so it is either not geting spark all the way to the plug or your timing is out (Chain jumped) When you pull the coil wire do you get GOOD spark? It should be able to jump about 1/2" gap to ground. If you have that, pull a wire off a plug, stick a screwdriver in it and hold it to ground and crank... watch for spark, it wont be as strong as it was at the coil wire but close to it. if no spark or weak, replace cap and rotor. It could be wires also but I'm assuming you dont want to spend money if not neccessary. If you do have good spark to the plug, pull a couple and make sure they arent gas fouled. Oh yeah, welcome to FTE

 

Thanks bashby.

The plug wires were all replaced last year so I kind of doubt it's them. I'll try your suggestions this evening.

 

Here are the results: Pulled the coil wire and the spark jumped over a half an inch. I didn't understand what you meant about putting the screw driver in it but I did pull a spark plug wire and held it to the engine. It jumped there too, just not as far as the coil. I then pulled two spark plugs. They smell strongly of gas and both are black everywhere. Other than the black color and gas smell, they look close to how they did when I replaced them about a year and a half ago. They are all Motorcraft ASF 32C plugs. (Cool side note: they are made in the USA!)

Here are a couple of pictures (Same plug but they both look the same).







I connected both plugs to the wires and cranked to see if I had spark at the plugs themselves. One of them jumps between the little gap like its supposed too. However, the other one seems to be sparking inside itself because I see light coming out around the 'base'. I swapped the plugs to the opposite wires to rule out the wires or distributor cap as causing the problem. It is definitely that spark plug.

Does the black indicate 'gas fouled' plugs? What's next in that regard?

I also ran the Voltage test at the high pressure pump again. I'm sure of the readings now. I set it to read Volts and after turning the key to 'on' I get a brief reading of '2.1 V' then it shows '0F' and another brief reading of '2.1 V'...then it drops to zero. This happens within about a second...two at most.

Unless I'm misinterpreting the meter, I'm nowhere near the required 12 V for the pump. Any recommendations for my next step on this part of the problem?

 

Those plugs dont look too bad but the one sparking up inside indicates a crack in the porcelin, I'd go ahead and replace them. It should have ran off of starting fluid, maybe you didnt spray enough in it. I'd replace the plugs and confirm if it will run on starting fluid. 2v isnt enough to run the pump, I've seen relays get to were they only allow partial voltage to whatever they run (burnt contacts inside)

 

If you believe the engine might be flooded, hold the gas pedal to the floor and start cranking it. This will put the computer in the "clear flooded engine" mode, and will turn the injectors off.

If you find it does try to start, and think the engine is getting too much fuel, first thing to do is pull the vacuum line off the fuel regulator. The regulator is mounted on one of the hard metal lines feeding the injectors. If you have fuel in the vacuum line, then your fuel regulator is bad.

If that looks ok, then your fuel injectors may be dirty and dribbling fuel into the engine. Plugging in a good fuel cleaner into the fuel system may help that problem.

And as always, with a fuel injected engine always pull the codes. If you are going to work on this thing, from now on, learn about the fuel injection system and how to pull the codes. The computer is your friend and will tell you stuff it thinks is wrong with any sensors on the engine.

 

Thanks bashby!

I'll replace the plugs and see what happens. I went to rock auto parts and it shows two different plugs available (ASF32PF4 & ASF32CF4). Does it matter which I choose...if so, why? EDIT: I found out that one is the copper core version and the other is the platinum. Still am wondering if choosing one over the other will matter though.

If the fuel pump is only getting two volts, how is gas getting to the engine? (The strong gas smell on the plugs.)

I can test the fuel shutoff relay by running a jumper wire to bypass the relay...is that correct? I made a modified relay according the the FSM instructions for testing the fuel pump...I may be able to use that.

Thanks Dave!

It does tend to 'try' to start sometimes. When should I check the pressure regulator's vacuum line for gas? After I crank it or can I simply pop the hood and check it right away? I went here and found out how to get the codes. I'll check them tonight.

If I hook up one of those remote trigger starters, will it throw off my troubleshooting results? The instructions for the remote starter say to disable the regular starting system by disconnecting the wiring harness and coil wire from the coil, and placing a jumper from the coil wire connector to an engine ground. Using one of these would really help me out because I wouldn't have to have my wife come out and turn the key to see if I have spark all the time...

Does anyone have a recommendation for a quality circuit test light?

 

Platinum is a tougher but more expensive metal, so those type of plugs last longer than the others.

Cycle the key on and off a few times without starting the truck. You should hear the pumps kick on. That will build pressure in the system, and then pull the vacuum line off.

The remote starter people are telling you to do all those wiring mods because they don't want the engine to start. The remote starter is mostly used for turning the engine over without it cranking up. But if you want to use it to start the engine you can. Turn the keyswitch to run, and then crank the engine over remotely, but be careful, it could start at anytime.

 

So there is no need to be concerned about poor performance if I go with the platinum ones for longevity? Both of the plugs show as original equipment for the truck when it rolled off the assembly line. I don't really understand that though because you can only have one or the other on the truck...maybe they used both for different versions of the truck.

I've actually never heard the pumps on my truck. There is a noise similar to a fan that comes from the passenger side but nothing at the high pressure or in-tank pumps. Maybe it has to do with the electrical problem at the high pressure pump. (only 2 Volts are reaching it.)

Thanks for the words of caution. I mainly do need it to just turn over so I can watch for spark on my own. Without pushing in the clutch and turning the key, if at all possible.

I'm getting a fuel pressure tester that will work w/o a diagnostic valve on Friday so I can do those tests as well.

 

I was working on replacing the spark plugs and started checking the distributor cap stuff. Here is what I found.










What is this part?


A closer look at the cracks:


Questions are:

1. From what you see above what do you recommend I replace?

2. What is the correct resistance for a spark plug wire in good condition? I measured three of mine. One was 13.5 Ohms, 2nd was 10.5 & the third was 7.8 Are those OK or do I need to replace the wires too?

3.Can petroleum jelly be used in place of dielectric grease?

Thanks for all the help so far!

 

That cracked piece is the pickup for the ignition system. Replace that and see if it will start. Here's a picture of it. It's about $20.00 at the parts store.

http://contentinfo.autozone.com/znet.../F122/image/4/

The stuff in the other pictures are worn, but shouldn't keep it from starting. The cracked piece may be the problem.

 

Thanks for the help. Well, no one near me has that part for $20. They start at about $45 and go up. Ford dealership was willing to sell me one for $180!! Talk about sticker shock.

Anyway, I started checking into just replacing the entire distributor with a re-manufactured one and it looks like a better value for my money.

So, while getting ready to take out the distributor I took off the air hoses & cover for the throttle linkage at the top of the engine.

Here is what I found:




This looks like four wires connecting in a poor manner or just really bad corrosion.



This connects from the wire harness to the TFI module connector.



I'm not sure what it does yet...


but it's not looking good is it?


I'm attempting to verify power to the EEC Module but have been unable to find the 'EEC-IV module vehicle harness connector' to test pin 57 to ground.

Will someone please tell me where I should be able to find it or possibly have a picture of one?

 

bump.

Does anyone know what this connector is? The autoparts store had no idea what it is. The Haynes manual says its the 'SPOUT' connector and to disconnect it when doing initial timing.

The wiring diagrams show that spout wire going from the TFI module to the EEC IV but there is no information on what its for.

I'm also still looking for the EEC IV module and test area if anyone has an idea.

 

The spout connector is there so you can set the timing.

The computer controls the timing, and sets it exactly where it wants it at any particular time. But it has it's limits and can't adjust but so far. So you disconnect the spout connector, and this takes timing control away from the computer so you can set it according to the sticker on the radiator. This gets the dist in the "ballpark" so when you hook the spout back up, the computer has full range of control.

If you try to turn the dist to set the timing without disconnecting the spout, the computer will "fight you" and move it back electronically to where it knows it should be set.

 

The explanation you gave is very helpful...thanks Dave!

So its basically a connector located where it is to make it easier to properly set the timing. Looks to me like I can replace it with any standard one wire connector, provided it uses the same gauge wire.

If there is any harm in me cutting it out and replacing it with my own, please let me know.

Do I need to pull my instrument panel to get to where the EEC-IV module test area is? I see a slew of wires going up there from the firewall into the cab but they connect into something I can't access. I pulled the mask but it doesn't open up access like I thought it would.