[madcowintucson]

I think its the immobilizer, but nothing i check confirms this. the car started and ran fine , but i just had to replace the ignition swithc. pulled car into garage, swapped out swith all the elctrical problems resolved, but then car wouldnt start. vcds has no fault codes, engine is getting fuel and turns over, just wont fire.

please any suggestions?

 

[Fluid]

You should be able to swap ignition switches without a problem. They don't need syncing. Also, it's not the immobilizer because it'll still let the engine start - it just shuts the engine off immediately. This is a TDI right? If the glow plug light isn't on you have a bad relay 109. If the battery is too low the engine speed sensor won't let the engine fuel.