"1997 Volkswagen Polo: Imobilier Stopping Vehicle from Starting"

Silver 1997 Volkswagen Polo Left Side View

I have a 1997 Volkswagen Polo which has being playing up only recently. Previously (as in a few months ago) i would get in the car weather its hot or cold and it would start first time no problems. Recently the car has being playing up a lot. I get in the car and turn the key and nothing happens. I hold it in start position for 20+ seconds and nothing.. The starter motor makes no effort to do anything. All lights on dash come on as per normal and all electronics within the car work as per normal. The only way to get the vehicle going is by moving the key to off position and trying to start it again. After 5 painful minutes it usually gets going. I have disconnected the battery for 24 hours to try to reset ECU however it didn’t make a difference at all. Could someone please help! I have the original Volkswagen key with a transponder black chip thing on it. Also i have a Sony stereo unit which beeps a lot when you have just switches the ignition off? would this be causing problems? Thanks for your help.

Answer: How old is the battery? If it is 5+ years old then it is near the end of its life. When you try for 20 seconds this can strain the battery a lot. It is better to try for about 5 seconds and then give the battery about a 30 second rest before starting again.
The first place to start is to check that the battery is in working order. Use a multimeter to measure across the positive and negative. It should read no less than 12.6 volts when the vehicle is off. This also means that the battery is holding at least 75% of its charge which would be good. Once you have eliminated the battery then its time to move on to the other issues.

Popular faults that can cause what you describe are:
- Cam shaft sensor
- Lambda sensor
- Fuel pump
- Fuel pump sensor
- Engine speed sensor

So it could be wear and tear. It sounds like it considering it is a 1997 model.