Okay, I 'scanned' my car with the paper clip trick and came up with a code 26. This is the code for the evaporative emissions solenoid. The manual says that the ecm sends different frequencies to the evap solenoid to help with the fumes and emissions. What exactly would go wrong with this? I checked all the wiring, I checked the actual canister, and they both appear to have no cracks or tears. I do not hear it turn on, but maybe there is just enough pressure in the tank. I enev tried removing the gas cap, driving around and then returning it. The ses still comes on. Anyone have any ideas? I might just take it to the dealer and tell them to fix it.

Jay

 

The EEC canister solenoid is "on/off" modulated.... the ECM swithces it on and off to achieve a particular "duty cycle" for the solenoid, to adjust flow. All the ECM is looking for is a complete circuit, with some resistance in it, representing a healthy solenoid. If you get the code, could be because the solenoid is bad. The ECM can not see what is happening anywhere else in the system, whether there is flow or not, etc. It just looks for a complete circuit. Make sure you have power to the solenoid.

Your 93 is also different, in that the high current loads like the solenoids, are driven off a seperate module, called the "Quad Driver". Sometimes the driver in that module can fail. That's why most code lists for 93's don't show "EEC purge solenoid" for DTC 26. They show "Quad Driver #1 circuit".

 

Thank you Mr. Injuneer, I think I understand the problem a little better now. I am still confused on what I should do to fix the problem, though. Any suggestions?

 

I guess you just need to find out if the solenoid is "good". There should be a "resistance" spec for it, but I don't know what the spec is. Check the manual, or post the question for "Shoebox"... he knows the details of a lot of the parts and pieces.

You also need to make sure there is power to the solenoid. I'm looking at a 95 wiring diagram, but these things are often very similar, if not exactly the same. You should have a brown wire to the solenoid, and a dk green/white stripe wire going to it. The brown wire should have +12V, from a fuse in the underhood box. You will only have that power when the ignition is switched to "on".

The dk green wire is the one that goes to computer (ECM). The ECM supplies a "ground" to operate the EEC solenoid. Problem is, the EEC solenoid only seems to get opereated when the engine is under load. So you could try and blow thru the solenoid when it is not activated, and no air should flow. Apply +12V to the brown wire, and ground the dk green wire, and the solenoid should open and let air flow thru. If that works, you need to verify the wire from the ECM to the solenoid is not broken, shorted or has a corroded terminal in the connector.

 

Thanks Injuneer