Originally Posted by Zfbod94
Courtesy of Injuneer: 26 - Evaporative emissions canister purge solenoid circuit.
I see that you replaced the Evap solenoid already. Did you check the wiring for the circuit. Im not sure what voltages you need to look for, but you can at least check for continuity in the circuit. Im sure someone else can chime in on what voltages you need to look for.
No. That's the code description for 94/95. The 93's are different. The ECM incoporates several "quad driver modules".... used to operate high amp circuits like the solenoids. DTC 26 in a 93 is (courtesy of Shoebox):
Quad-Driver Module (QDM) #1 circuit
- AIR pump relay circuit
- EGR solenoid
- EVAP solenoid
In all cases these are based on electrical circuit continuity. In the case of the AIR pump, all it is checking is the fuse in the AIR pump circuit. You can just unplug the AIR pump, put a good fuse in the circuit, and not get a code for the system. Check the fuse.
For EGR, it is only checking the EGR solenoid circuit, as described above. EGR system could be totally removed, except for the solenoid, and you don't get DTC 26 (you could get DTC 32 for EGR system performance). No need to clean or replace the EGR valve unless you also have DTC 32.. It's for the solenoid electrical circuit. Could be the wiring or conector since you replaced the solenoid.
Key on, check for 12V on the brown wire to each solenoid harness connector. The ECM provides the ground to open the solenoid.
I beleive DTC 26 would also set if the QDM #1 in the ECM is defective, but not sure. I looked it up in my 93 shop manual and it does indicate cause could be "faulty ECM".
Shoebox's code list - note that the 93 codes, where different from 94/95 are shown on the right side of the chart.