How can I thoroughly and successfully clean dielectric grease from the O2 connectors?
Thinking I was doing a good thing I used dielectric grease on my O2 connectors. Oops. I've confirmed what I now recall having heard before but always discounted -- that the O2s actually use the little bit of air that can make its way down the wires from the connectors, traveling between the copper and the insulation. Amazing, but so I now learn, true.
I tried cleaning the connectors with electrical contact cleaner. Repeatedly. Still no luck. The truck starts and runs seemingly well, but the UltraGauge shows short-term fuel trim of +25, indicating the ECM is getting no signal from the sensors and interprets it as a lean condition. But because the voltage is zero or near zero, the ECM gives up after a minute or two, shows STFT at 0.00, goes into open loop and throws the P0130 and P0150 codes.
So today I installed two new Bosch 15175 O2s and took the truck for a test drive. Success!
Or so I thought. The fuel trims looked normal on the mile and a half test drive, but when I left to meet a friend a half hour or so later they were back to +25, then 0.00 STFT, open loop, codes, SES light, yada, yada, yada. (BTW I know I could set up the UG to read O2 voltage directly, but I think the +25 STFT clearly tells the story).
I've again disconnected the connectors and sprayed liberally with contact cleaner. The new sensors were obviously clean when installed, but there must have been just enough grease still in or on the harness-side connector to contaminate the connectors on the new sensors.
I'll reconnect and drive the truck either later tonight or tomorrow and see what happens, but in the meantime does anyone have any other ideas to try? I REALLY don't want to have to replace the harness-side connectors.
Thinking I was doing a good thing I used dielectric grease on my O2 connectors. Oops. I've confirmed what I now recall having heard before but always discounted -- that the O2s actually use the little bit of air that can make its way down the wires from the connectors, traveling between the copper and the insulation. Amazing, but so I now learn, true.
I tried cleaning the connectors with electrical contact cleaner. Repeatedly. Still no luck. The truck starts and runs seemingly well, but the UltraGauge shows short-term fuel trim of +25, indicating the ECM is getting no signal from the sensors and interprets it as a lean condition. But because the voltage is zero or near zero, the ECM gives up after a minute or two, shows STFT at 0.00, goes into open loop and throws the P0130 and P0150 codes.
So today I installed two new Bosch 15175 O2s and took the truck for a test drive. Success!
Or so I thought. The fuel trims looked normal on the mile and a half test drive, but when I left to meet a friend a half hour or so later they were back to +25, then 0.00 STFT, open loop, codes, SES light, yada, yada, yada. (BTW I know I could set up the UG to read O2 voltage directly, but I think the +25 STFT clearly tells the story).
I've again disconnected the connectors and sprayed liberally with contact cleaner. The new sensors were obviously clean when installed, but there must have been just enough grease still in or on the harness-side connector to contaminate the connectors on the new sensors.
I'll reconnect and drive the truck either later tonight or tomorrow and see what happens, but in the meantime does anyone have any other ideas to try? I REALLY don't want to have to replace the harness-side connectors.