Car turns over and immediately dies - 77 Ford Mustang II Base 2.8L V6

ToniOhio

Member
May 24, 2021
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Cincinnat, Ohio
Hello, really looking for help. My 16 yr old just bought his first car. It has been sitting for 7 years (garage kept). He replaced battery, mechanical fuel pump, inline fuel filter, rebuilt the carb, checked vacuum lines, new spark plugs, new fuels, etc., tried using fuel directly from the gas can and we still can't figure out what is the problem. I really would appreciate if someone is able to offer suggestions. Was not able to locate any kind of fuel fuse or relay.. not sure if there is one on this car, but don't think that is the issue any way. Would love any all suggestions. As mentioned in subject, the turns overs and starts but then immediately dies.
 
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Enzio

Dang it. I was hoping mine would get 3 more inches
May 14, 2019
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Hi and welcome to the forum. First off I'll let you know right off that pictures will be asked for a lot! So you may as well send one right away. Secondly we can't tell from your post what size engine etc. So, some more info would work well for the experts on this forum. (I'm not the expert) They'll chime in I'm sure.

I suspect the rebuilt carb as from what you stated that would be the most drastic thing you've done. Do you still have the parts left over from the rebuild? Check to see if there's something that should be installed but got left out. I'm just throwing stuff out there but is the float set right? Does the car start on its own or are you putting fuel in the carb to start it?

I'll let the experts take over now.

They'll want pictures too.
 

LILCBRA

I wish I didn't have all of these balls in the air
15 Year Member
Dec 6, 2005
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Hello and welcome! :)

I'm going to go back to basics and go from there. An engine needs 3 things; fuel, air and spark. Is it getting spark? If it's not then there are a multitude of issues it can be. If it's getting spark, is it timed correctly? If so, then it's a better than average chance fuel delivery is the issue. I'm going to guess just by what you've shared that that's probably not the problem, but we can't rule it out completely. And, technically, the engine needs 4 things, the last being compression. If it's a compression issue there are most likely larger problems that will need addressed before it'll run.

And you're right, there is no fuel fuse/relay on these cars. Those are used for fuel injected cars with electric pumps which was a few years after the IIs were discontinued.
 

2Blue2

will be trying this sex one when I can find it
Mar 5, 2019
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Sounds like a weak coil / bad ground issue
 

ToniOhio

Member
May 24, 2021
5
1
13
38
Cincinnat, Ohio
Hi and welcome to the forum. First off I'll let you know right off that pictures will be asked for a lot! So you may as well send one right away. Secondly we can't tell from your post what size engine etc. So, some more info would work well for the experts on this forum. (I'm not the expert) They'll chime in I'm sure.

I suspect the rebuilt carb as from what you stated that would be the most drastic thing you've done. Do you still have the parts left over from the rebuild? Check to see if there's something that should be installed but got left out. I'm just throwing stuff out there but is the float set right? Does the car start on its own or are you putting fuel in the carb to start it?

I'll let the experts take over now.

They'll want pictures too.
Car starts on its own with no fuel in carb but immediately dies, I hear one cylinder fire then dies.
 
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ToniOhio

Member
May 24, 2021
5
1
13
38
Cincinnat, Ohio
Hello and welcome! :)

I'm going to go back to basics and go from there. An engine needs 3 things; fuel, air and spark. Is it getting spark? If it's not then there are a multitude of issues it can be. If it's getting spark, is it timed correctly? If so, then it's a better than average chance fuel delivery is the issue. I'm going to guess just by what you've shared that that's probably not the problem, but we can't rule it out completely. And, technically, the engine needs 4 things, the last being compression. If it's a compression issue there are most likely larger problems that will need addressed before it'll run.

And you're right, there is no fuel fuse/relay on these cars. Those are used for fuel injected cars with electric pumps which was a few years after the IIs were discontinued.
Sounds like a weak coil / bad ground issue
How could this be tested?
 

ToniOhio

Member
May 24, 2021
5
1
13
38
Cincinnat, Ohio
Hello and welcome! :)

I'm going to go back to basics and go from there. An engine needs 3 things; fuel, air and spark. Is it getting spark? If it's not then there are a multitude of issues it can be. If it's getting spark, is it timed correctly? If so, then it's a better than average chance fuel delivery is the issue. I'm going to guess just by what you've shared that that's probably not the problem, but we can't rule it out completely. And, technically, the engine needs 4 things, the last being compression. If it's a compression issue there are most likely larger problems that will need addressed before it'll run.

And you're right, there is no fuel fuse/relay on these cars. Those are used for fuel injected cars with electric pumps which was a few years after the IIs were discontinued.
Hello and welcome! :)

I'm going to go back to basics and go from there. An engine needs 3 things; fuel, air and spark. Is it getting spark? If it's not then there are a multitude of issues it can be. If it's getting spark, is it timed correctly? If so, then it's a better than average chance fuel delivery is the issue. I'm going to guess just by what you've shared that that's probably not the problem, but we can't rule it out completely. And, technically, the engine needs 4 things, the last being compression. If it's a compression issue there are most likely larger problems that will need addressed before it'll run.

And you're right, there is no fuel fuse/relay on these cars. Those are used for fuel injected cars with electric pumps which was a few years after the IIs were discontinued.
Carb bowl fills and stay fills and jets squirt when peddle is pressed. Tested all spark plug wires and spark plugs replaced. How would I check the timing?
 

7991LXnSHO

10 Year Member
Sep 1, 2010
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There are spark checkers you can put at the end of a plug wire and ground to see the strength of a spark. The resistance of the coil can be measured against specs.

So if it was firing, then dying as soon as you let off the key, I would suspect the run power wire to the ignition. I do not know what version of Duraspark you have and how it’s wired. But dating back to the days of points, there has been a power wire for starting and another for run. While looking for a diagram, I’d also verify there is power at the primary side coil in the run position.
 
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LILCBRA

I wish I didn't have all of these balls in the air
15 Year Member
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Here's what @7991LXnSHO is referring to. It's probably a good place to start and not horribly expensive.

Amazon productView: https://www.amazon.com/dp/B06X1DNHDK/ref=cm_sw_r_cp_apa_glt_fabc_7R89XK5YGQVV6XW11G16


Another quick and easy check for timing is to pull the distributor cap off and check the location of the rotor compared to the #1 plug position on the cap. It should either be pointing in that direction OR the opposite direction if the timing mark on the damper is at or very near top dead center. It wouldn't hurt to crank the engine momentarily while the cap is off to be sure the distributor is turning as it should, too. To the best of my knowledge the 2.8 engines have a plastic or nylon timing gear set. It is possible that the gears have worn and are not turning the camshaft. I'm no expert on the 2.8, but I think the distributor is turned by the cam in the same way a 302 is, so if the distributor isn't turning that will tell you a lot about the gearset.
 
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jozsefsz

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Aug 11, 2013
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Lots of good suggestions above but....

If it's starting then it's getting fuel and spark.
The circuit to the coil + has two paths. The first is from the starter solenoid - while you're cranking that is powering the coil. Full 12V.
After the car starts (key moved back to run not start) it will get <12V from the ignition circuit through a ballast resistor.
I'd suspect the second part has something wrong - could be ignition switch, wiring, or the resistor itself.

Easy to test - use a test-light or multi-meter at the coil + and check for voltage with the key in the run position.
If no voltage, jump a wire from battery + to the coil + and try to start the car. If it stays running, you've found the issue.
Make the wire easily removable - it will be your only way to shut off the car if it starts running.
Don't run it this way forever - the ballast resistor keeps from prematurely cooking the coil. Keep it disconnect after shutdown or it'll drain your battery and cook the coil.
 
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