Lennox GHR26Q3-75-1 furnace. After intermittent burner firing, I removed the ignitor yesterday and cleaned it with steelwool. I did this after reading this recommendation from other posts I've read here, with similar problems. After cleaning it, the burners fired right up about 4-5 times. This morning, same problem. Furnace starts normal cycle, but no ignition. Before I pulled the ignitor again, I noticed the spark was very low. I removed it and again cleaned it with steelwool. It fired right up with a much stronger spark. The furnace was installed 1/96. Only service work since was in '97 when they cleaned the ignitor and sensor, after having same problem as now. Could it be just time to replace the ignitor? Thanks for any help.