Engine shutting off

[BigGump]

1990 F 350 Crew Cab Long Bed 4x4 460 Engine.
So this problem has been messing with me for a while. I will be driving along and the engine will just shut off like i turned the key off. Sometimes it will start back up and run like nothing happened until it does it again. Other times it will die then struggle to start and run until it finally starts and will run great for how ever long it likes. I do notice that when its about to have an issue when you put the blinker on the volt meter drops and raises a lot. also when it does not want to restart and struggles it smells as it has gas going to the engine like its being flooded. Also most times when i start it i really have to turn the key hard. i replaced the ignition switch i first bought the truck for this issue but has come back. Any fresh ideas would be awesome.

 

[BigGump]

so last night i replaced the ignition swith on the steering column and had found a wire where someone had put a butt connector and never crimped it properly, i was sure this was the issue. after replacing the switch it is now easier to start the truck and the transmission is also shifting alot better. But on the way to work this morning the engine died again. so back to the drawing board.

 

[O'Rattlecan]

Hmm, interesting set of symptoms. I have to ask... Have you pulled codes on the vehicle? The computer will tell you what it's thinking or seeing.

Ryan

 

[flareside_thunder]

Pull the TFI module and have it tested at the parts store. Oldfordfuelinjection.com for how to pull codes.

 

[BigGump]

I pulled codes before and had an egr code but have since repaired that issue and when this happens I don't get any new codes. Today I went ahead and replaced the ignition control module.

 

[flareside_thunder]

Any change? When the TFI gets heat soaked it does the symptoms you described above....so does the coil.

 

[kiwi f150]

I'd be checking all the earthing connections you can find as it's likely with the age of your truck they are probably starting to corrode and deteriorate.
Undo the earthing connections then wire brush them clean bright and shiny then reconnect ..... sometimes i've even been anal enough to use an electrical grease (diaelectric grease) under the harder to reach earthing points as it saves revisiting them later.

I've found "poor earths" to be the main causes of electrical faults in vehicles i've owned either producing a direct fault or having been the cause of a component failing.

 

[BigGump]

After replacing the ignition module it has done it again. I have checked the grounds before an have also replaced the coil with no improvement. I researched the TFI MODULE and couldn't find the part for my truck. If I'm correct it's on the distributor right? But after it leaving me on the side of the freeway for two days in a row I have dropped it of at my buddy's shop.

 

[smokey]

Check on your left fender apron that is where some were mounted

 

[BigGump]

Yes that is where the ignition module was so this sounds like the same thing.

 

[BigGump]

well my truck has been at the shop for a week now and the said the distributor was bad so they replaced it, test drove it and it ran good for about ten min then started running rough and died again. After getting it back to the shop they found the timing was advanced to 40 degrees when they had set it to 10 degrees. So they reset it and drove it again and had the same results. Their telling me it needs a timing chain and gear set. What do you guys think, is that something that would intermittantly happen. And would it just make the truck shut off as if you turned the key off?

 

[flareside_thunder]

They do know that they have to pull the spout connector out to properly set the timing, right? If it had jumped time, it wouldn't be an intermittent issue. Has anyone found any codes on it? I'm thinking its a clogged idle air control valve.

 

[dustybumpers]

I would bet on the coil. It's heating up, and shutting down, only to start right up after it cools off.

 

[Fellro]

Timing chains don't intermittantly cause trouble, then refire. When they hop, you are down. No run, then die, then start up fine and then die again. It is electrical or fuel, nothing with the mechanical aspects of the motor. Commonly the tfi ignition module will pull a game like that, but already went there without changing much.

 

[BigGump]

Thanks guys. I have it back now and will pull the codes tomorrow. I have replaced the coil already with no change. And I will reset the timing by the book. I just got to a point where I was at my wits end last week. Do you guys think a computer could cause this? They said they pulled an ignition code and a torque converter slip code.

 

[primetime]

Will it act up if you just let it sit and run, ie your driveway? If so start wiggling stuff, like wiring connectors and fusible links.

Remember, just because it`s new doesn`t mean it`s good. Especially with all this made in China CRAP that is foisted on us these days.

Don`t rule out items such as your fuel pumps, relay, transfer switch, and inertia switch.

Intermittant problems like this really suck. I feel for you.

 

[BigGump]

So today I it up pulled te codes which it had a few. Set the timing by the book and test drove it. There is a huge difference with the new distributor( burn outs with 37 inch tires). But I keep getting codes for the TPS and EGR Sensor, I tested them per the book and all ok. I still feel the computer could have and issue. So I will put more miles on it and let y'all know.

 

[flareside_thunder]

Pull your idle air control valve off and see how crapped up it is.

 

[Ridgerunner]

Pull your idle air control valve off and see how crapped up it is.

I agree and cleaning them is only a temporary fix.

 

[flareside_thunder]

Temporary, yes...but its better than just throwing parts at it. Real mechanics diagnose and troubleshoot.