Pelican Parts Forums - 81 SC Oxygen Sensor Relay

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Quote:

Originally Posted by mca (Post 5210672)

Just wanted to add to this discussion for others in the future.

Yesterday I had a strange cold start issue. It was running really lean, rough and the idle was low. Not driveable.

I pulled my air filter and lifted up on the sensor plate. Strangely the car recovered and immediately acted normal. I just figured that my sensor plate was getting sticky and wasn't able to lift enough to richen the mixture during the cold start.

So I drive off and everything is perfectly normal. About 20 minutes later (in a SHADY part of town) my idle dropped like a rock at a stoplight. I limped off of the road and into a parking lot. The car was again running VERY lean. Spitting, popping and not driveable.

After talking to a local Pelican on the phone I swapped my 02 sensor relay (always carry a spare). Car ran perfectly after that. I drove it at least 60 miles today and it was flawless - including the cold start.

Now for my question ... how do I remove the orginal relay from under the seat? I am not familiar with how it is attached to the bracket - don't see any way to remove it. Tips anyone?

Thank you posting about solving this problem. You've saved me. For about 12 months I've suffered an intermittent problem of sudden rough idle and poor acceleration, back fires, the works. It happened again today. My SC has been running well for a few months and today after filling up the gremlins were back. It was drivable but only if I used light throttle and didn't lug the engine.
A quick trip to the auto parts store before closing time for a new relay and now it's running better than it's ever been. Best $12.99 I've ever spent.

is this relay needed with a car without a O2 sensor? my 82 does not have cat or o2 sensor and I am trying to figure out how the previous owners made it run that way.

Thanks,

Quote:

Originally Posted by 82 SC (Post 9495579)

is this relay needed with a car without a O2 sensor? my 82 does not have cat or o2 sensor and I am trying to figure out how the previous owners made it run that way.

Thanks,

My 82SC was set up like that when I acquired it, well almost. Still had the cat and O2 sensor but it was all disabled. I surmise the previous owner had just set the mixture very rich. The wiring to the Frequency Valve was absolutely charred; the wiring from fuse #6 (if I remember correctly) was not attached to power the ECU and the relay was toast. Fixed the wiring to the ECU and a new relay then tuned the mixture and all was well. Then the charred wiring to the Frequency Valve must have shorted as that took out the ECU one day. Sourced another ECU, fixed the wiring to the Frequency Valve and it has been fine since. The car is much more drivable when the system works like it was designed to work.

By far, the easiest method to find out if the O2 relay is functioning is to reach under the passengers seat and hold it in your fingertips while starting the engine. A good one you will feel a "click" and a bad one you won't feel anything. They also get a bit warm after driving for a while.

good to know SCadaddle. Mine drives ok, some idle issues sometimes. to me most likely vacuum issues. will check the relay the next time i drive it. :)