Golf does not start when it has sat in the sun

[JJackson]

My Golf 1.4 TSI 122 does not like starting when it has been left out in the sun all day. Starts in the morning fine then when I leave off work does not like to start and when it does start revs really high. Has anyone else experienced this. Has been to garage but computer has shown no known faults.

[WeegieBob]

If the car is still under warranty JJ take it back and get them to check it again.

There's something wrong and I'd put money on it it'll be some sensor that's not doing its job or being too sensitive. I'm sure one of the members here will have much more specific experience than I have and will give you a more detailed response.

[Keithuk]

Well this is a strange one. There are only three reasons why any engine won't start at anytime.

1) Mechanical damage e.g. cambelt broken, unlikely.

2) Insufficient spark (compression/temperture in a diesel) to ignite the mixture.

3) Insufficint fuel (or diesel) to sustain combustion.

In your case there are various sensors on the engine to monitor these different conditions, engine temperature, ambient temperature etc

The fact that it only happens when the temperature is warm may mean that the engine could be flooded with fuel. Have you tried giving it full throttle when the engine won't start? This will clear out most of the excess fuel.

I'm sure most of these can be checked with VAG-COM. ;)

[HHGTTG]

"no known faults." What a cop out this is for our overly complex cars, nowadays.

Our cars do develop faults and all VW (and others) can say is that well worn phrase. But just where does that leave us and our expensive motors? All the dealers can do is to keep on replacing units that MIGHT be responsible until the fault is eliminated and sometimes that can be never.
The only solution then, after frustrating visits to the dealer, is to pass on your car to some poor unsuspecting soul who sees you 'old' vehicle on some dealer's forecourt, all nicely polished but hiding all sorts of gremlins.

Progress?? - pah!!

[Vincent Vega]

Take it to the dealer for the same time you arrive at work, and ask them to leave it out in the sun all day and try and start it at the time you leave. Perhaps then their diagnostics will show something.

Or find a friend with a VAG-COM/VCDS cable and do the same thing yourself.