Migs7

***87/F150/4.9***

My issue is a 84 EGR Vacuum Solenoid circuit failure

Here is the testing procedure.
DN13:
CHECK EVR CIRCUIT FOR SHORT TO POWER OR GROUND.
1.Key off.
2. EVR solenoid disconnected.
3. Breakout box installed,
4. PCM disconnected.
5. Measure resistance between Test Pin 33 and Test Pins 37 and 57 at the breakout box.
6. Measure resistance between Test Pin 33 and Test Pin 40 and 60, 46 at the breakout box.

Is each resistance greater than 10,000 ohms? No, no resistance at all.

If No - SERVICE short circuit. REMOVE breakout box. RECONNECT all components. RERUN Quick Test. If DTC is repeated, REPLACE EVR solenoid.))



FYI:All other parts of the test above were passed except for this last part; I did not skip any portions and I don't have any resistance at all when testing these pins.

((((To clarify i wasn't supposed to jumper 37/57 or 40/60 and test resistance at the jumper was I?))))

It just doesnt make sense that I would test at 33 here is why.. If you check out the diagram for my truck below you will find that pin 33 is connected to the EEC and to the EGR Vacuum Solenoid connector, there is nothing else in between. Here is the part of the test that is throwing me off... the test says that the connector at the EGR Vacuum Solenoid needs to be disconnected ... so how are you supposed to get any resistance? How would anybody ever get any resistance at any other pin if we have isolated ends of the this one wire???

What am i missing?

Migs7

Yo Fellas

Did some more testing based on the test mentioned above. Also found some diagrams that I'll post below.

As mentioned above the only Code I am getting is Code 84: EGR Vacuum Solenoid circuit failure.

Looking at the diagrams below, the circuit for the EGR involved a bunch of different wires. These wires are the grounds at pins 40 and 60 that go to the battery negative, 33 is the green Grounding wire for the EVR. I checked for continuity at all ends of these wires that show they are connected.

I am not sure how pin 46 is related to the EVR circuit, any ideas?

Based on my findings, other than the chance that pin 46 is causing the problem, I think that replacing the ECU is going to clear the code.

Migs7

Tested for continuity at pins ECM pins 26 27 46 and the corresponding pin connectors at the EGR Position Sensor. Continuity is there and im still getting Error code 84.

Here is a shot of the inside of the ECM... i had a water leak on the drivers side of the windshield last winter and didnt think about it till i saw the corrosion you see in these pictures.

Code 84 seems like minimal damage to the ECM if it really is water damage thats pushing the code on my code reader.

After testing all the wires related to the EVR and not finding a short anywhere, the ECM seems like the last part of the puzzle.

I'll get the ECM and then update this thread with the results.

Migs7

Replaced the PCM and now getting code 32 and 95.

32 orc EVP voltage below closed limit

95 oc Fuel Pump circuit open - EEC processor to motor ground (fuel pump unplugged or wiring damage)

I know the fuel pump is bad because when the tank is full it pegs to the "F" and stays there till about a 1/4 tank is left.

Code 84 seems to have been a similar problem to the true code that I am fetting now with code 32.

Any ideas?

Migs7

With the 32 error showing up I decided to replace the EVP and the issue was fixed.

I also removed and replaced the connector at the EVR, but im pretty sure the issue all along was the EVP.

I have not taken it for a long drive, but with the KOEO test the code cleared and now im only getting the 65 error (indicating the fuel #2 Fuel pumps is bad).

no other codes. Success.

tomorrow i'll be running the KOER test (hoping that only gives me a error 65 and no other gremlins come up)

some of the symptoms i've experienced is lack of power up hill and slow to accelerate. Matter of fact, up hill it was actually losing power and speed.

I'll update tomorrow with the results of the drive and Engine running test.