Pulled codes... ideas? [Finished...EVAP Delete]

[willwren]

Paul, considering the high impedance input of a voltmeter, the load during the measurement is negligible, and therefore, even with a single strand or two remaining in the conductor, full potential would be measured. He used a meter to determine the voltage across both pins of each device in that manner.

To test my conclusions, measure the resistance of a 12" long piece of multi-strand wire in the 16-20 gauge range. Then open the insulation in the middle, and cut away all but a couple strands. Measure the resistance again, and I bet it won't rise more than 1 or 2 ohms. 1 or 2 ohms will make pretty much zero difference in the voltage dropped by the circuit as detected by a meter.

There's a 95+% chance it's a loose or corroded ground. Not damage to a wire.

[kmalinich]

Paul, considering the high impedance input of a voltmeter, the load during the measurement is negligible, and therefore, even with a single strand or two remaining in the conductor, full potential would be measured. He used a meter to determine the voltage across both pins of each device in that manner.

To test my conclusions, measure the resistance of a 12" long piece of multi-strand wire in the 16-20 gauge range. Then open the insulation in the middle, and cut away all but a couple strands. Measure the resistance again, and I bet it won't rise more than 1 or 2 ohms. 1 or 2 ohms will make pretty much zero difference in the voltage dropped by the circuit as detected by a meter.

There's a 95+% chance it's a loose or corroded ground. Not damage to a wire.

This is exactly what I'm thinking. I'll post results when I get at the PCM grounds. I'm gonna take some pics too.. you'll need them to understand i think.

[Archon]

Basically, what you need to do is get the wire that goes to ground from each solenoid to the proper connection at the PCM. What Wren is saying is that it is better to try to find where the problem is with the current wiring, and fix it instead of splicing in a new wire for each running from the solenoids to the PCM. Though splicing will work, you run the risk of those connection corroding too, and will likely occur more quickly that the original wiring.

[kmalinich]

Okay. Final Update bump. Lemme sum this up real quick for ya.

Got all the wiring to the PCM handled. Redid PCM ground. Solenoid harness showed correct voltage in both open and closed operation with Tech2.

Purge solenoid turned out to be shot. Fixed that. Still EVAP leak somewhere and accompanying vacuum leak. I was very irritated.

It's the connection at the tank. I was fed up with this EVAP bullcrap.

Two words... EVAP Delete.

New vacuum setup...AN fittings... Had to custom fab one till I pick up the right one