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Car shut of while driving on hiway

  • Thread starter Thread starter Creomod
  • Start date Start date Aug 18, 2024
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Creomod

5 Year Member
Sep 14, 2018
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Aug 18, 2024
#1
  • Aug 18, 2024
  • #1
Ok guys I swapped out my alternator from my other car yesterday because I kept getting the battery symbol while driving. But I didn’t have problems. The light went away. So I thought everything ok . Just right now I was at my friends house and decided to go home . Car wouldn’t start. Looked at everything and nothing looked out the ordinary. Kept cranking car finally started. Drove fast going home on hiway and the car shut off going 80 lights on everything stayed on then it kicked back on. Did it twice. What would cause that? Ran codes did get a 54 but I don’t think that would cause that. Any input much appreciated……
Ran codes 18,31,85 also used noid light on injector blinking. Also used inline spark tester hooked it up on coil and it lit up so I have spark and noid light blinking so distributor good? Maybe the alternator causing car to shut off? Used different fuel relays does same thing. I am getting fuel pressure at 40 something when on
 
Last edited: Aug 18, 2024

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
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Aug 18, 2024
#2
  • Aug 18, 2024
  • #2
TFI module or PiP would be my guesses.
 
Reactions: Essn95, 89ripper, Creomod and 1 other person

Mindseye007

10 years still blowing strong
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#3
  • Aug 19, 2024
  • #3
TFI Module 100% cooked ,

get this TFI tester to test your current one from eBay works amazing and don't forget to buy a 9volt battery.

KASTAR 271a For Ford Ignition Module Tester Tfi Edis 6 Pin EEC-iv USA | eBay

Find many great new & used options and get the best deals for KASTAR 271a For Ford Ignition Module Tester Tfi Edis 6 Pin EEC-iv USA at the best online prices at eBay! Free shipping for many products!
www.ebay.ca

Then if needed buy a new TFI Module from Rockauto.

Motorcraft TFI
https://www.rockauto.com/en/moreinfo.php?pk=5434788&cc=1134010&pt=7172&jsn=17

STANDARD MOTOR PRODUCTS LX223 TFI for Manual 5 Speed Transmission.
More Information for STANDARD MOTOR PRODUCTS LX223

and you can relocate your new TFI module with this, best one out there.
https://www.mccullyracingmotors.com/

get some extra Arctic Silver 5 thermal paste
https://www.ebay.ca/itm/16642480345...pid=5335821607&customid=&toolid=10001&mkevt=1

and after its all installed your stang will fire right up and drive beautifully.

also if you ever need your ECU repaired this place is awesome and the best place to get it fixed at.


1986-2004 Ford Mustang A9L A9P ECU Repair Service​

1986-2004 Ford Mustang A9L A9P ECU Repair Service Engine Computer Repair Please fill out the R&R form here once you've placed your order.Easy repair process1. Purchase repair service (this way helps us keep track of what's coming in for repair)2. Include order number with your computer and mail...
www.theecuexchange.com
 
Last edited: Aug 19, 2024
Reactions: Creomod

Creomod

5 Year Member
Sep 14, 2018
530
43
48
45
San Antonio,Texas
Aug 19, 2024
#4
  • Aug 19, 2024
  • #4
Thanks guys. Ecu was sent there for that service couple years ago . So y’all don’t think these are bad alternator symptoms then ?
 

89ripper

Founding Member
Jun 3, 2002
926
308
103
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Rockford, Illinois
Aug 19, 2024
#5
  • Aug 19, 2024
  • #5
Defintely sounds like a tfi module problem. Only one way to know is test it or swap with known good one. Possible you are dealing with 2 different problems
 
Reactions: Mindseye007, Creomod and General karthief

Creomod

5 Year Member
Sep 14, 2018
530
43
48
45
San Antonio,Texas
Aug 19, 2024
#6
  • Aug 19, 2024
  • #6
Mindseye007 said:
TFI Module 100% cooked ,

get this TFI tester to test your current one from eBay works amazing and don't forget to buy a 9volt battery.

KASTAR 271a For Ford Ignition Module Tester Tfi Edis 6 Pin EEC-iv USA | eBay

Find many great new & used options and get the best deals for KASTAR 271a For Ford Ignition Module Tester Tfi Edis 6 Pin EEC-iv USA at the best online prices at eBay! Free shipping for many products!
www.ebay.ca

Then if needed buy a new TFI Module from Rockauto.

Motorcraft TFI
https://www.rockauto.com/en/moreinfo.php?pk=5434788&cc=1134010&pt=7172&jsn=17

STANDARD MOTOR PRODUCTS LX223 TFI for Manual 5 Speed Transmission.
More Information for STANDARD MOTOR PRODUCTS LX223

and you can relocate your new TFI module with this, best one out there.
https://www.mccullyracingmotors.com/

get some extra Arctic Silver 5 thermal paste
https://www.ebay.ca/itm/16642480345...pid=5335821607&customid=&toolid=10001&mkevt=1

and after its all installed your stang will fire right up and drive beautifully.

also if you ever need your ECU repaired this place is awesome and the best place to get it fixed at.


1986-2004 Ford Mustang A9L A9P ECU Repair Service​

1986-2004 Ford Mustang A9L A9P ECU Repair Service Engine Computer Repair Please fill out the R&R form here once you've placed your order.Easy repair process1. Purchase repair service (this way helps us keep track of what's coming in for repair)2. Include order number with your computer and mail...
www.theecuexchange.com
Click to expand...
Hey brother I just bought that tfi tester you sent me from eBay. Do I have to remove the tfi or can it be tested installed? Dose t say anything on discption
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
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Aug 19, 2024
#7
  • Aug 19, 2024
  • #7
Hey! Don't forget to pickup one of those little tools for installing/removing the screws for the TFI.

It makes life easier than trying to find a thin-wall socket that fits.
 
Reactions: Creomod and Mindseye007

Mindseye007

10 years still blowing strong
5 Year Member
Oct 21, 2020
579
135
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Aug 19, 2024
#8
  • Aug 19, 2024
  • #8
Creomod said:
Hey brother I just bought that tfi tester you sent me from eBay. Do I have to remove the tfi or can it be tested installed? Dose t say anything on discption
Click to expand...
Actually you have to unplug the tfi from the distributor because you need to probe the 3rd prong you will see in the instructions. Don't forget to buy a 9volt battery.
 
Reactions: Creomod

Creomod

5 Year Member
Sep 14, 2018
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San Antonio,Texas
Aug 19, 2024
#9
  • Aug 19, 2024
  • #9
Update! I removed the alternator to have it tested & it failed. I know we are thinking it might be the tfi/distributor wondering if it was the alternator reason why it didn’t want to start then shut off on hiway & then kicked back on again?
 

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89ripper

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Aug 19, 2024
#10
  • Aug 19, 2024
  • #10
Didnt you switch this alternator out?
 

2000xp8

SN Certified Technician
Aug 8, 2003
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#11
  • Aug 19, 2024
  • #11
I have my doubts this is an alternator issue. The car will run without one until the battery is dead, then it dies and won't restart.
 
Reactions: Mindseye007

Creomod

5 Year Member
Sep 14, 2018
530
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San Antonio,Texas
Aug 20, 2024
#12
  • Aug 20, 2024
  • #12
2000xp8 said:
I have my doubts this is an alternator issue. The car will run without one until the battery is dead, then it dies and won't restart.
Click to expand...
Your right i just turned around going to work it tried shutting off and backfired gotta be distbutor
 

Creomod

5 Year Member
Sep 14, 2018
530
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San Antonio,Texas
Aug 20, 2024
#13
  • Aug 20, 2024
  • #13
89ripper said:
Didnt you switch this alternator out?
Click to expand...
No I put the other one I had it’s good/passed it’s the distbutor it just backfired and tried shutting of on me
 

89ripper

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Aug 20, 2024
#14
  • Aug 20, 2024
  • #14
The tfi module is in a bad spot in its stock location. It overheats and will start to cause problems. Some of us on here have relocated it (like mindseye suggested).
 

Creomod

5 Year Member
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Aug 20, 2024
#15
  • Aug 20, 2024
  • #15
I just swapped to a different distributor still wants to stumble shut off. I checked coil has light both sides key on. I’m gonna swap the fuel regulator see if that helps. I also have had a raw fuel smell while driving. I removed the vacuum hose off the regulator don’t see fuel. Only other thing I can think of is ignition switch or fp.By the way the distbutor in my hand I just removed it and that’s the one that car was shutting off with and backfired on me this morning
 

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Creomod

5 Year Member
Sep 14, 2018
530
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San Antonio,Texas
Aug 20, 2024
#16
  • Aug 20, 2024
  • #16
Questions.
Would car shut off while driving if bad fuel regulator?
Car shut off while driving intermediate bad coil?
Would car shut off while driving bad /intermediate fuel pump?
 

90sickfox

Wasn't a pretty sight...and I've got big hands
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#17
  • Aug 20, 2024
  • #17
Check the computer ground by battery. A bad fuel pump relay or pump can cause cut off issues but not common to fail that way. TFI usually has to sit and cool down before restarting. If your coil is shorting you should be able to see it in the dark reving engine. Sometimes you can see spark jump. Usually, will cause weak spark or no spark. I'd ohms test the coil and clean all the ground connections. I'd also check the ignition switch wires and switch body for looseness or overheated contacts.
 
Reactions: Creomod and 2000xp8

Creomod

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San Antonio,Texas
Aug 20, 2024
#18
  • Aug 20, 2024
  • #18
90sickfox said:
Check the computer ground by battery. A bad fuel pump relay or pump can cause cut off issues but not common to fail that way. TFI usually has to sit and cool down before restarting. If your coil is shorting you should be able to see it in the dark reving engine. Sometimes you can see spark jump. Usually, will cause weak spark or no spark. I'd ohms test the coil and clean all the ground connections. I'd also check the ignition switch wires and switch body for looseness or overheated contacts.
Click to expand...
How can I see it in the dark for the coil? What is spark jump? Fuel relay I bought 2 weeks ago along with o2 sensors.ignition switch was swapped about 6 months back along with sp wires. Now one thing I will say o know car running lean cuz I see it on the plugs and I have been driving with bad afr gauge sensor but not sure if that’s why it’s cutting off and that’s why I was suspecting the fuel pressure regulator
 

Potomus Pete

I'm still waiting for the fully nude shots
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#19
  • Aug 20, 2024
  • #19
What?
 

2000xp8

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#20
  • Aug 20, 2024
  • #20
I'm inclined to think it's a connector or loose wire/ground somewhere also.
Probably not going to be fun to track down.

The reality is that it would be easier to fix if it was plain old broken.
 
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