Engine dies intermittently

[Gary202]

1989 Bronco w/302 manual Vehicle starts fine and I can drive it a little ways and then it dies. I've towed it home twice and when I get it home it will start. Got it to a shop and they said vacuum hoses(2) were not connected. I drove it home and The diagnosis doesn't spend right. Will. Vacuum hoses cause these symptoms.(the mechanic said these older vehicles are hard to work on).
Thanks
Gary

 

[Tiha]

Most likely it is ignition module. Could also be a failing fuel pump.

Get a spark tester. I like the one pictured below. When it dies, see if it has spark. Put it on, leave it on. They are cheap.

Has spark? Yes, fuel pump problem, or at least check fuel pressure.

No spark. Then a igniton module or pickup module problem.

We used to dump a bottle of water on the ignition module to cool it down. If it restarted then we know.

 

[miesk5]

Yo Gary,
As Tiha advised and Try a Self Test for Diagnostic Trouble Codes by my pal, BroncoJoe19 @ Code Reader.....
The engine temperature must be greater than 50° F for the Key On Engine Off (KOEO) Self-Test and greater than 180° F for the Key On Engine Running (KOER) Self-Test. Run it around to heat the engine up and shift thru all gears including Reverse. Make sure A/C is off and transmission is in Park (automatic); or in Neutral for a Manual and; release clutch. Then turn off engine, all accessories/lights (close driver's door) , etc.

Do KOEO test First. Post Code(s) here according to KOEO and KOER.

A helper can assist you by counting the codes. Some use their smart phones to record them.

BEWARE OF FAN, BELTS, PULLEYS, HOT HOSES, IGNITION HIGH TENSION WIRES, AND ENGINE COMPONENTS⚠

Or ask local mom and dad parts stores if they will test it for you.

Or purchase a coder reader such as Equus 3145 Innova OBD I Code Reader for Ford EEC IV Engines at Walmart & most parts stores.

See my vacuum leak test in post #21 @ https://www.broncozone.com/threads/...-and-running-code-44.23994/page-2#post-125535

 

[Gary202]

Most likely it is ignition module. Could also be a failing fuel pump.

Get a spark tester. I like the one pictured below. When it dies, see if it has spark. Put it on, leave it on. They are cheap.

Has spark? Yes, fuel pump problem, or at least check fuel pressure.

No spark. Then a igniton module or pickup module problem.

We used to dump a bottle of water on the ignitiView attachment 31399on module to cool it down. If it restarted then we know.

Thanks, much appreciated!

 

[Gary202]

Yo Gary,
As Tiha advised and Try a Self Test for Diagnostic Trouble Codes by my pal, BroncoJoe19 @ Code Reader.....
The engine temperature must be greater than 50° F for the Key On Engine Off (KOEO) Self-Test and greater than 180° F for the Key On Engine Running (KOER) Self-Test. Run it around to heat the engine up and shift thru all gears including Reverse. Make sure A/C is off and transmission is in Park (automatic); or in Neutral for a Manual and; release clutch. Then turn off engine, all accessories/lights (close driver's door) , etc.

Do KOEO test First. Post Code(s) here according to KOEO and KOER.

A helper can assist you by counting the codes. Some use their smart phones to record them.

BEWARE OF FAN, BELTS, PULLEYS, HOT HOSES, IGNITION HIGH TENSION WIRES, AND ENGINE COMPONENTS⚠

Or ask local mom and dad parts stores if they will test it for you.

Or purchase a coder reader such as Equus 3145 Innova OBD I Code Reader for Ford EEC IV Engines at Walmart & most parts stores.

See my vacuum leak test in post #21 @ https://www.broncozone.com/threads/...-and-running-code-44.23994/page-2#post-125535

Thanks a lot! I think this will help.

 

[paul rondelli]

If you do not know the last time the fuel pump was replaced ..... go ahead and replace it. They are a common failure point .... the pump works it's ass off providing fuel to the EFI system. The fuel in the tank is how it cools the pump ... if you constantly run the tank under a 1/4 it doesn't cool the pump well...... and at over 3.00 a gallon who rides around with 26 gallons in the tank?


As stated above the PIP sensor provides RPM data to the ECU. The distributor is another mechanical device that works it's ass off. It spins at 3,000 RPM's for 25+ years..... eventually it starts to wear out. As it wears out...it produces more heat..... the extra heat shortens the life span of the PIP sensor mounted on the side of the Dizzy. The Bronco will run fine while cold... and won't throw a code. Once you run her for a while the heat in the dizzy starts to increase ..... and the PIP fails and sends bogus information to ECU. My 1996 with a 5.0 and a stick would stumble at full throttle... after warm up. I replaced all the usually electrical suspects ( cap,coil, wires) without any difference. Once I replaced the entire distributor .... she ran like dream... and has been awesome ever since.

keep an eye on the tachometer ... if the tach goes really crazy.... that is what the ECU is seeing. On cold start watch the tach..... and see if it behaves any differently on a failure start up when hot. The wire coming off the PIP sensor goes to the ECU and directly to the tach.

 

[Kreechure]

1989 Bronco w/302 manual Vehicle starts fine and I can drive it a little ways and then it dies. I've towed it home twice and when I get it home it will start. Got it to a shop and they said vacuum hoses(2) were not connected. I drove it home and The diagnosis doesn't spend right. Will. Vacuum hoses cause these symptoms.(the mechanic said these older vehicles are hard to work on).
Thanks
Gary

Older vehicles in my opinion are easier to work on. And, yes. From my experience vacuum lines can cause all sorts of problems but, usually just running rough. Not dying.

 

[Kreechure]

Older vehicles in my opinion are easier to work on. And, yes. From my experience vacuum lines can cause all sorts of problems but, usually just running rough. Not dying.

Is it fuel injected or carburetor?

 

[Motech]

When it stalls, disconnect your SPOUT connector, the ignition timing connector near your distributor. If it starts, or seems to run better, then you have a bad pickup coil inside the distributor, the PIP sensor. Very common failure item on high mileage Ford, when they begin to fail, they fail only when hot.