Engine New to Mustangs, guidance needed on fault codes 47 & 45

Mustang5L5

Put lubricant all over the balls
Mod Dude
Feb 18, 2001
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Does the fuel pump actually run?

If so, more than likely the code is an artifact of not running the single wire from the pump relay to the ECU which it uses to monitor of the circuit is active.

This wire doesn’t exist on 87-88 harnesses, which is why it’s commonly added otherwise you get a false code 96
 
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sUdz6.0pwrstk

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Apr 9, 2021
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Yes. Fuel pump runs fine. Actually the car is running good other than it suddenly died at a stop light. The car has ran fine every since I ran the neutral switch harness away from the exhaust pipe. Like I said it only died once at a red light during an 8 mile test drive.

Went ahead an ordered a switch and harness. Should be here this week. Along with the switch I've ordered window regulator/ motor, guide bushings, moisture barrier, and lock solenoids.
 

Mustang5L5

Put lubricant all over the balls
Mod Dude
Feb 18, 2001
36,857
12,759
224
Massachusetts
If the pump is running, I’m going to assume the code 96 is due to wire harness issues. Specifically lacking the monitor wire to pin 19. This wire doesn’t exist on 86-88 harnesses

B419AAE1-7538-4A97-B801-42DC9E69D386.jpeg
 
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sUdz6.0pwrstk

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If the pump is running, I’m going to assume the code 96 is due to wire harness issues. Specifically lacking the monitor wire to pin 19. This wire doesn’t exist on 86-88 harnesses

Nice! I understand why would think that.

Would splicing from one end to the other be sufficient?
 

Mustang5L5

Put lubricant all over the balls
Mod Dude
Feb 18, 2001
36,857
12,759
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Massachusetts
Nice! I understand why would think that.

Would splicing from one end to the other be sufficient?

Yes. A single wire tapped onto the fuel pump relay to pin 19 will turn off that code.

However, as a sanity check, you may want to clear the codes and rerun them and see if it returns. Sometimes the code will store if the engine stalls out and will stay in memory. By wiping it and seeing if it comes back you can ensure it’s an active condition that the ECU is seeing
 
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sUdz6.0pwrstk

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Cleared the codes a few days ago. Getting code 11 past few scans KOEO. Thank goodness for now. Replaced both lock solenoids and window motors today. More test runs tomorrow. See if we can't get this car to chit the bed again.
 

manicmechanic007

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Sep 26, 2017
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Find yourself a used super star II or better yet a NGS to properly read codes
Use Ford wiring Diagrams free at public library on AllData
Replace or check the connector at the tank fuel pump module for code 96
Replace the stator in the distributor and retest for code 18
There is a reason you only see a few RX7's a year
Had several RX motors apart bag of worms do not pass go love the cars
 
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sUdz6.0pwrstk

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Haven't done much troubleshooting lately, just driving the stang here and there. Randomly dies every once in awhile.

After many passing codes(11), we've picked up a 14.

Now for the incident we had today...... 20211018_173822.jpg
That is the computer. We haven't tucked it up behind the dash due to all the troubleshooting we've done in the passed few months.

Today I ran to tracker supply to pickup fuel for the grill and I asked my daughter to ride with me. As we sit in the driveway at idle the car died. The car wouldn't restart. I see my daughters foot on the computer. She moves her foot from the computer and the sob started right up. I was like what the hell! I start the car and slightly move the computer, died. Repeated this multiple times and some while in gear.

I'll leave you with that.
Have a good evening.
 
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manicmechanic007

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Most likely a wire is loose or pulled out of the connector
Processor itself is most likely okay
Good luck
Take a six cell mag light and inspect the female pins in the connector and make sure they are all ok and in position
 
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Boostedpimp

15 Year Member
May 8, 2003
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If I was you, I would treat your daughter to something good because she saved you a ton of head scratching and stress.. Jingle each individual wire in that harness to the ecm until you find the culprit if you can't visually see the problem easily
 
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sUdz6.0pwrstk

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If I was you, I would treat your daughter to something good because she saved you a ton of head scratching and stress.. Jingle each individual wire in that harness to the ecm until you find the culprit if you can't visually see the problem easily
She definitely blessed us with some direction. I'll pick her up a 6 pack of Ale 8 after work. :nice:
 
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sUdz6.0pwrstk

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Apr 9, 2021
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Well we've found a loose connection. Pin #56 PIP. Give a little tug and she ain't happy about it.

Now i can't help but wonder how many more are like that and with that I have a question.

How do you release the wires on the connector??
 
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manicmechanic007

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Great job
You saved yourself several hundred bucks
Do tuck that processor back away now
Now you can enjoy your Mustang again
 

sUdz6.0pwrstk

Member
Apr 9, 2021
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Ky
Just updating the thread. I've been driving the stang like it was my daily. Taking to on longer runs to get temps good and warm. Basically try to get the car to chit the bed.

All is good. KOEO passes every time. The loose connection was the issue. Car runs super smooth. A true joy to cruise around in even though it looks like a turd. We'll start to begin body work this winter it seems. Thank you for the help and responding to my problem.

Cheers sudz
 
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General karthief

wonder how much it would cost to ship you a pair
Mod Dude
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I got over the 'shiney' chit a long time ago, anymore I just want to drive my crap, I've had 'shiney' and frankly, it's a pain, you hate to park it anyplace you can't watch over it, I do enjoy the wash and wax routine till you start see'n the nicks and scrapes from idiots with dangling keys, I even watched a kid set a soda can on my fender and walk away, even had a girl plop her butt on the fender to 'grab a selfie' with the car.
 
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