New O2 relay - still clicking.

[m_wuebben]

Hi gents - I replaced the O2 relay under the passenger seat of my '81 SC. It is still clicking, only when the gas pedal is not being pushed. If I hold it, I can feel it cycling, or what ever. Is the computetr going bad? Cheers, Mike.

[Mookster]

My '83SC went through this for 2 years intermittently. My vehicle would suddenly buck violently when driving down the road but it always stated with a LOUD clicking from the O2 relay under the passenger seat.

DO NOT THROW PARTS AT THIS PROBLEM!

Ask me how I know.

If the relay is just quietly clicking at low rpms or slow speeds, this was normal on my vehicle.

If I may suggest:

1. Replace the fuel pump relay. Clean and check the connections. If you don't know when the relay was replaced, consider this a must. The fuel pump relay can leave you stranded. Keep the old relay as a spare. Cost around $25.
2. If the fuel pump relay doesn't fix the problem remove the rev limiter relay behind the far left dash gauge (I believe it is the fuel gauge). the relay is has a plug in wiring harness and is about 2X3 inch in size. You can disconnect the rev limiter relay and the car will run without issue and it is free. Be sure not to push the envelope when driving because you can exceed red-line without a safety net. If the rev limiter relay needs to be replaced, kiss $350-$400 goodbye.
3. You can disconnect the o2 sensor in the engine compartment (left side near the fuel accumulator and low) and test to see if the sensor on the exhaust bung is going bad. Use the search function for more discussion on this topic and connection location.

If you car is still running when the O2 relay under the seat is clicking, open the hood and listen for the fuel pump relay clicking. If the fuel pump relay is also clicking, the rev limiter relay is shorting and attempting to stall your vehicle.

A good tune up is always a good thing as well.

I hope this helps. Keep us posted.

[m_wuebben]

Thanks, I will give those a try. Cheers.

[Mavitec]

I Mike,
I had the same problem on my 1983 cabriolet it was only the idle that was set too low; the oxygen sensor relay is getting its power from the fuel pump relay that is energised by the airflow sensor contact. When the idle is too low, the contact is triggering both relays. If you leave it clicking it will damage both relays. To adjust the idle you have to adjust the idle bypass screw to get 850 to 950 RPM hot.

Mario

[m_wuebben]

Thanks, I just had the idle adjusted down. Cheers, Mike.