cannister purge control solenoid questions

[mikem]

I am still trying to get this stubborn solenoid to work so that the CE light can be finally turned off. There is no power showing in to the solenoid so it must be either faulty wiring or control module. Any ideas on how to fix this? If it is the wiring can I slave a new wire into the control module; if it is the control module itself can I simply put a switched live to the solenoid (though I guess this wont switch off the CE light - will it?). Once I solve the problem will the light go off on its own or will I need to reset the system by disconnecting the battery?

[vrg3]

If there's no +12v power to the solenoid, then you should fix that before worrying about the computer.

Yes, you can run a switched live power wire (properly fused!) to the solenoid to replace the existing power feed if that wire is somehow damaged.

The computer controls the ground side of the circuit. It throws a trouble code if it doesn't have to sink enough current through this ground.

So if the problem persists after replacing the +12v side, you can consider running a new wire from the other side of the solenoid back to the computer.

[danj]

I was wondering what the symptoms of this problem are......for future referrence, other than the CEL code!
Thanks

[mikem]

Well can you believ it - I finally managed to sort this out. I unearthed the wires ging into the computer and simply pushed a few of them around and, hey presto, CE light no longer comes on! (other than during initial start up)
I am still not convinced that the solenoid valve is operating though, as when I pull off the plastic tube from the cannister ther is no evidence of suction. At what point should the solenoid open??

[scuzzy]

Well can you believ it - I finally managed to sort this out. I unearthed the wires ging into the computer and simply pushed a few of them around and, hey presto, CE light no longer comes on! (other than during initial start up)
I am still not convinced that the solenoid valve is operating though, as when I pull off the plastic tube from the cannister ther is no evidence of suction. At what point should the solenoid open??

the solenoid opens when vehicle speed gets above about 3-5mph


You can sit there and rev it all you want, but I've looked at the purge control (same thing) value in vrg3's scantool, solenoid only opens at speed.

so it's normal that you shouldn't feel any suction, feeling suction when the engine is idling and stopped means the valve has probably failed.

[vrg3]

You can check if the valve is actually moving by putting the ECU in test mode (connect the green connectors) and turning the ignition switch to ON. The ECU will cycle all the solenoids on and off, so if you feel the purge valve you should feel it click open and closed over and over.