A6_4.5

Hello, have a problem with my 4.2 First it died on me after driving for a while and now it will not start when warm at all.When i turn the key it cranks but does not start. Fuel pump good, new fuel filter. However no spark when it cranks. Does anybody knows which sensor respond for the spark? Please help!!!!

Redneck Truck

Check crank position sensor (on transmission bell housing) and camshaft position sensors (one on each head). They will cause a no spark condition if they are bad or disconnected, I believe. Also, a VAG-Com will help you immensely.

ALLDATAdiy INFO

Have you pulled any Generic OBD-II codes?

A6_4.5

Thank you-no there are no codes nor check engine light.

Thank you-i will check those sensors next time when it will not start.
Again-thank you for your responses.

jseklund

Most of the time, something like this leads me to check on the coolant temperature sensor...

Peter Badore

You should have a scan done with VAG-COM as some generic scan tools may not report fault codes properly.

A6_4.5

I have OBDII Bluetooth connector-do you know if it will work with VAG-COM? Also, which VAG-COM you referring to, when i went to get it, there are a lot of different versions-not sure what is the difference between them. Will you know if there is a free trial version to try?
Thanks

GTA_Driver

The free version should allow you to read all the fault codes. Why not give it a try?

You may also want to get a cheap USB cable from eBay for some $10-$20. And if you have questions, give RossTech a call - it won't cost you.