2003 VW Passat
Starts fine when overnight temp is above ~15 degrees. If below this, car will not turn over at all, no clicking noise. Battery tests OK.
Any idea what might be wrong?
Hit the starter with something that can deliver a moderate dead blow… if you can reach it.
Yes, that often works, but is usually not a good permanent solution. On a Ford I used to emply a hockey stick which would just pass through all the gear and hit the starter. Use the straight part of the stick!
So you think this may be a problem with the starter? Again, there is no problem starting above a certain temperature, but if everything is cold enough, then nothing moves nor makes any noise at all.
Yes, either the starter is going, or possibly a bad connection, I’d check all the connections first. My older VW had a poor ground between the engine and body, I don’t know if that might be the problem with yours.
What is the battery terminal voltage when it doesn’t start? What is the voltage on the outside of the battery cable terminal? What is the resistance, in ohms, between the negative battery terminal and the car body or engine block? Hooo boy! Is that voltmeter ever handy, or what?!