Q7 2007 3.0 TDI Starting Issues
 

Hi everyone,

So I've been having some issues with my beautiful car recently, it's almost temperamental you'd say. It will start in the morning first go (8:10) but, if I turn the engine off and attempt to restart immediately it will not start, sometimes for 40mins, 2hrs, 7hrrs, 24hrs.. The Emission light (engine light) will stay on while the engines tries to start. It cranks but doesn't kick in that last 5% where the engine actually starts. When the car does start, runs perfect, not drops in idle nor while driving at any point. Unfortunately it's not giving off ANY error codes which has cost me a fair bit of money trying to find where the fault is.
I have replaced all filters, cleaned fuel tank, serviced vehicle and still the issue persists. My mechanic has mentioned it could be the fuel pressure system?
I'm thinking more a sensor (fuel or exhaust) or the fuel injectors?

Any help would be greatly appreciated