Pulled codes...what do they mean?

[Hethj7]

I pulled these codes today in the KOEO test:

Hard code:

67 - Manual lever position sensor out of range, neutral pressure switch switch circuit open ( my car is a 5 speed)

Continuous memory codes:

31 - EVP or PFE circuit below minimum voltage

66 - TOT sensor signal input below self-test minimum or vane air flow circuit below minimum

96 - Fuel pump secondary circuit fault, high speed fuel pump relay open

I don't know why code 67 would matter much and am not sure what would cause the code 96. What is the EVP or PFE circuit and what is a TOT sensor? Where do I go from here? Thanks!

[PKRWUD]

Code 67 is because you didn't hold the clutch pedal to the floor during the test. If you did, then it could be because of a problem with your a/c circuit, or because the a/c was on during testing. More than likely, you didn't hold the clutch pedal to the floor during testing.

Code 31 means there's a problem with your EGR valve, or more specifically, the sensor that measures it. Disconnect the harness at the EVP sensor, and jump the brown/green wire and the orange/white wire. Run KOEO self test again, and look for a code 35. Ignore all other codes. If a code 35 comes up, replace the EVP sensor.

Code 66 means there's trouble with the MAF. It usually happens because someone unplugs the hose that goes to the oil fill tube from the TB, or because of a loose clamp holding the MAF, or the tubes, in place. Inspect them all and make sure it completely sealed. Next, inspect the electrical connector to the MAF, and make sure it's clean and tight.

Code 96 means your fuel pump relay is on it's way out, or the power wire to it has a bad connection. I would replace the relay, and inspect the wires.

Take care,
~Chris

[Hethj7]

Thanks Chris! You always come though on this type of stuff.

[Hethj7]

Where is the EVP sensor located?

I have never replaced my EGR valve. Should I go ahead and do that regardless of if the sensor is good or bad? I have heard that sometimes it will cause problems without a code showing up.

[TMASTER]

EGR Valve Position (EVP) directly monitors valve position to control EGR flow. Its the little canister looking thing that bolts to the back side of the EGR plate.

[Hethj7]

Thanks! I have to run to work so can't fool with it much more today, but I just fixed my MAF code and the fuel pump relay.

I got a code 11 (passed) after clearing those two codes. I will still look into my possible EGR problem though.

I then got a code 91 for the key on, engine running test afterwards. I think this is HEGO sensor out of range/system lean. What does this mean? Thanks for the replies!

When I have time I will re-run the KOEO test, as I kind of hurried through it since I have to get to work and may have missed something.

[Hethj7]

Anyone know what do to about the code 91?

[PKRWUD]

Code 91 means that your drivers side O2 sensor is reading lean. Since the right side is reading normal, that rules out a vacuum leak or a fuel pressure problem. Likely causes are a bad O2 sensor, or a bad injector in cylinders 5-8. If you don't have a miss, it's the O2 sensor. If you do have a miss, do a power balance test, and see which cylinder it is.

[Hethj7]

Thanks! I will check into it.