The Ford Focus not starting was a intermittent problem that I had been dealing with for years. The car in question was a MK1 Ford Focus but I think the problem and the symptoms I experienced would be the same for any car not starting.
The fix for me was a new starter motor.
Why did I wait so long to get one?
Starters motors are not cheap and I wanted to be 100% sure the starter was the problem before I bought one for no reason.
Lets dig into the problems I had so you can see if you situation is similar.
Sometime the Focus would start, sometime it wouldn’t. The car not starting was in the form of the engine not turning over on the key. Fuel pump would come on, lights on the dash all on as normal but the car would not turn over. When the problem was experienced, most of the time it wouldn’t even try to turn over and occasionally it would turn very slightly and then stop.
In cold weather it was pretty good, it would start ninety five times out of a hundred but in hot weather or if I had just been sitting in traffic it was hit and miss. The hotter the weather or the longer I had been sitting in traffic, the more likely it would be that the problem would surface. The only solution was to let the car cool down.
First I tried changing the battery, maybe the one I had was weak. No difference.
I checked the wiring, even going so far as to wire the starter directly to the battery with a switch mounted inside the cabin and this helped a lot, for a while ie most of the times it didn’t start on the key it would start on the button. Looking back I believe the starter had lost efficiency and direct wiring gave the starter just enough extra power to turn the engine.
Until finally even the button didn’t work. It became hit and miss on the key and on the button and in cold conditions and hot.
At this point I was happy with the battery, I was happy with the wiring, there was only one thing left to change and that was the starter motor.
With the new starter installed the improvement was obvious immediately. The engine turned over much faster and the new starter seemed about twice as powerful as old one.
And another thing I noticed was the voltage drop when starting the engine. With the old starter the voltage might drop down to 9 volts or maybe less, with the new starter the voltage doesn’t go below 10 volts.
Granted the old motor had seen probably over 200,000 kms of service so I can’t complain too much that it finally gave out and to be fair to it, it was making an effort right until the end!