I recently noticed two zones just spitting water instead of staying on when in "automatic" mode. I pulled one valve apart, cleaned it and it still isn't working right. I can hear the solenoid on the other zones that are working, clicking but on these zones the solenoid goes much slower. I replaced one valve with a Rain Bird and it now works fine. I thought it might be the solenoid so I replaced it on the other valve and it still is just spitting water. I took the valve apart, cleaned it, inspected it for damage, put it back together but it still isn't working right. Any ideas?