I have a 2006 Forester. It has low mileage, approx 26K. A few weeks ago I notice that occasionally I had to crank longer than normal for the car to start, but not every time. I replaced the battery as it was the original 5 year old battery and tested low, but that did not solve the problem! Then one time the check engine light came on for a second and went off. I Did not come on again, except at start up. Now in order to start the car quickly, I have to pull off the clutch slightly. I have generally started the car in gear, but think I should be starting in Neutral. When I started in neutral this morning it seemed to start more reliably? Maybe just a coincidence? Is the Interlock Switch going? I got down and played with the switch a bit, checking movement and such. I believe there is a way to D/C the switch and jumper it to the harness to see if bypassing the switch works, to rule out the switch? I am assuming that the harness is the plug with multiple contacts to the right of the switch. The interlock switch is on the bottom of two switches on the clutch, right? Is that the one that would need to be replaced if there is a problem. Please help if you have any experience with this.

On my 2002 Forester, the clutch interlock switch prevents the starter-motor from turning. No juice to the starter relay.

 

It doesn't have anything to do with the ignition circuits. In other words, the interlock would not prevent the engine from firing, if it was already turning over.

The clutch switch prevents power from reaching the starter solenoid when the clutch pedal is not depressed. This means the starter will not turn if you don't push the pedal down.

 

The car is 5 years old at this point, even if it hasn't driven far there are still some things that could use attention. Spark plugs could be worn. Fuel and air filter could need to be changed if they haven't been. Run a tank or two of premium gas or a bottle of strong fuel system cleaner such as BG 44K to clean fuel injectors. A can of Seafoam in the gas tank works for that also.

 

Cars with such low mileage often can have mouse nests under the hood. Tight spaces and good shelter form the elements make perfect hiding places for rodents. Check for wires or vacuum hoses that might be chewed on.