Engine Trouble Codes( With Video)

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Did you initiate the code reading process? Or is it doing that on it's own?

Usually a blinking CEL (on it's own, not during the rear process) indicates a pretty bad misfire.
 
Code 31 is most likely the reason for the blinking Check Engine Light. This system really doesn't have the ability to monitor a misfire. Try running the codes with the engine running.
So am I reading "all" of the codes correctly? I think I see 1 blink then a pause, but there's no code for the number 1. Thanks for looking at the video
 
Code 31 is egr related, and 87 and 96 are fuel pump relay related.

The code 31 would display the check engine light.

Did you delete codes engine off and then engine on? After the engine on codes are done blinking, blip the throttle and it will start the cylinder balance test. At the end, it will blink codes again. 9 is pass. Any other blinks identify which cylinder is giving issues.


Part of why I like the innova 3145 code reader. You get numbers rather tha counting blinks.

So, Im assuming this car is mostly stock? Is the egr still there? Can you clean/inspect it?

Also any reason why the fuel pump relay would give you two codes? Any modifications to the pump?


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Code 31 is egr related, and 87 and 96 are fuel pump relay related.

The code 31 would display the check engine light.

Did you delete codes engine off and then engine on? After the engine on codes are done blinking, blip the throttle and it will start the cylinder balance test. At the end, it will blink codes again. 9 is pass. Any other blinks identify which cylinder is giving issues.


Part of why I like the innova 3145 code reader. You get numbers rather tha counting blinks.

So, Im assuming this car is mostly stock? Is the egr still there? Can you clean/inspect it?

Also any reason why the fuel pump relay would give you two codes? Any modifications to the pump?


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If the egr is next to the passenger header with a vacuum line to it that ran from the smog pump, I removed it. I have a fuel pump kill toggle switch wired to the relay under the driver seat so I can shut off fuel when parked. I believe the pump is stock. I will do KEY ON ENGINE RUNNING tomorrow.
 
I'm going to guess toggle was off when you ran codes? If so, that accounts for those two codes.

Egr is bolted to the intake spacer and points to the firewall. There's a vacuum line running to it.

Removing the smog pump line will generate two codes, both of which come up with the engine running codes. Both are harmless codes

so far code 31 looks to be the source of your check engine lights


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I'm going to guess toggle was off when you ran codes? If so, that accounts for those two codes.

Egr is bolted to the intake spacer and points to the firewall. There's a vacuum line running to it.

Removing the smog pump line will generate two codes, both of which come up with the engine running codes. Both are harmless codes

so far code 31 looks to be the source of your check engine lights


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No...toggle was on(I heard fuel pump prime) left it on when I warmed up engine for test. I'll probably just replace egr valve and 02 sensors. Thanks for your replies. I really appreciate it.
 
No...toggle was on(I heard fuel pump prime) left it on when I warmed up engine for test. I'll probably just replace egr valve and 02 sensors. Thanks for your replies. I really appreciate it.

Replacing the EGR sensor or valve most likely will not fix the 31 code.
CODE: 31
(KOEO) - EVP circuit below minimum voltage. Vref (5 volt reference voltage supplied by the computer) missing or broken wire or bad connection in circuit.
Revised 06-Aug-2016 to add clarification of the 10 pin connector possible problems
Use a DVM to check for 5 volts on the orange/white wire. If it is missing, look for +5 volts at the orange/white wire on the TPS or MAP sensor located on the firewall near the center of the car. Use the black/white wire for the ground for the DVM.
With the sensor removed from the EGR and still connected, press the plunger and watch the voltage change on the brown/lt green wire. Pull the passenger side kick panel and measure the voltage at the computer. You will need to remove the plastic cover over the wires and probe them from the backside. A safety pin may prove very useful for this task. Use pin 27, EVR input (brown/lt green wire) and pin 46, signal ground (black/white wire) to measure the voltage. The orange/white wire is Vref and should always be 5 volts -/+ .25 volt. Be sure to measure Vref at the EGR sensor to rule out any broken wires or bad connections.
Measuring the voltage at the computer helps you spot broken wiring and intermittent connections. The 10 pin connectors are especially prone to connection problems, If the voltage checks at the EGR sensor are good but not at the computer, the 10 pin connector is suspect.
See the graphic for the 10 pin connector circuit layout.
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Code 87 – fuel pump primary circuit failure. The fuel pump lost power while the engine was running. Check fuel pump relay, check inertia switch, wiring to/from inertia switch, red wire going to inertia switch for +12volts. Check the other side of inertia switch for +12 volts.

Diagram of the fuel pump wiring for 86-90 cars
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Diagram of the fuel pump wiring for 91-93 cars.
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Code 96 for 86-90 model 5.0 Mustang – KOEO- Fuel pump monitor circuit shows no power - Fuel pump relay or battery power feed was open - Power / Fuel Pump Circuits. The fuel pump lost power at some time while the ignition switch was in the run position. The main power feed to the pump is what is losing power.

Look for a failing fuel pump relay, bad connections or broken wiring. The fuel pump relay is located under the passenger seat. On Mass Air Conversions, the signal lead that tells the computer that the fuel pump has power may not have been wired correctly.
See http://www.stangnet.com/tech/maf/massairconversion.html

Look for power at the fuel pump - the fuel pump has a connector at the rear of the car with a pink/black wire and a black wire that goes to the fuel pump. The pink/black wire should be hot when the test connector is jumpered to the test position. . To trick the fuel pump into running, find the ECC test connector and jump the connector in the lower RH corner to ground.
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86-90 Models:
Using the diagram, check the red/black wire from the fuel pump relay: you should see 12 volts or so. If not, check the inertia switch: on a hatch it is on the drivers side by the taillight. Look for a black rubber plug that pops out: if you don't find it, then loosen up the plastic trim. Check for voltage on both sides of the switch. If there is voltage on both sides, then check the Pink/black wire on the fuel pump relay: it is the power feed to the fuel pump. Good voltage there, then the fuel pump body to tank wiring harness connector is the likely culprit since it is getting power. No voltage there, check the Orange/Lt blue wire, it is the power feed to the fuel pump relay & has a fuse link in it. Good voltage there & at the Pink/black wire, swap the relay.

Keep in mind that the relay wiring and socket can also cause intermittent problems. Clean the relay socket with non-flammable brake parts cleaner or electrical contact cleaner. If you find damaged wiring at the relay socket, replacement pigtail socket assemblies are available at the auto parts stores. Be sure to solder the wires and cover the solder joints with heat shrink tubing if you replace the relay socket.

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If your running the computer and sensors that require an egr valve and all the fuel related items. You will need to put back the egr valve. Is your vehicle running proper? Run a fuel pump pressure test at rail. Should be at least 35 psi. Check for power in and out of inertia switch, their should be twelve volts. Also make sure all grounds are good.


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If your running the computer and sensors that require an egr valve and all the fuel related items. You will need to put back the egr valve. Is your vehicle running proper? Run a fuel pump pressure test at rail. Should be at least 35 psi. Check for power in and out of inertia switch, their should be twelve volts. Also make sure all grounds are good.


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He can leave the valve off. It will not effect anything.
 
If your running the computer and sensors that require an egr valve and all the fuel related items. You will need to put back the egr valve. Is your vehicle running proper? Run a fuel pump pressure test at rail. Should be at least 35 psi. Check for power in and out of inertia switch, their should be twelve volts. Also make sure all grounds are good.


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Yes.. The car is stock. All the pieces are there except for the smog pump. I'm going to redo the codes and make sure toggle to fuel pump relay is on. Egr is there, I'm going to try to clean it out. Now that I think about it.. I ran out of gas a week ago..car shut off/ key on coasting to stop. Maybe that's where the fuel pump code comes from.