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I have had a new battery fitted in the car, a Vauxhall Corsa - alternator and started motor checked but the car is still having trouble starting.
Not sure what year your Corsa is, but I would think it does have a On Board Diagnostics. If you can, get it hooked up to an analyzer to see which codes it is giving you. That would definitely narrow it down. Disregarding engine size, the things to check are airflow sensor, crankshaft sensor, idle speed control valve and exhaust gas recirculation valve. Any of those can cause you considerable grief. Check the air filter and vacuum connections for any leaks and that they are on. Poor starting on those engines is often caused by idle speed control valve and most definitely the crankshaft sensor. As you can see there are numerous issues that could cause this. Of Course you also want to make sure that your fuel pump and fuel filter are working or replaced. You can download a Repair Manual for your vehicle from here. Hope this helps and clarifies it a bit. Good luck.
I had this problem. I discovered that the nut which clamped the wiring harness to the alternator was loose which caused intermittent connection from the alternator to the car’s electrical system including the battery. Tightening the nut down fixed the problem.
you should check for voltage drop on battery leads (measure at battery post not clamp) as I have had this in the job I do.