Purchase 2002 Volvo C70 from private owner with 150,000 miles. Replace the turbo pressure valve by the airbox, The car ran very rough, I parked it returnre the car another day and now it will not start. I was very careful when disconnecting the vacuum hoses. I turn the key several dash lights are on but will not start. I do not hear a tick tick tick sound nor do I hear the fuel pump sound when I turn the key. what should I do next please help

 

if you are not hearing the engine turn over, first step is to check battery voltage and then try to jump start the car. I wouldn';t think the turbo pressure sensor or boost valve would keep the car from turning over - and I'd think it would only be in play once the engine is producing boost.

 

Thanks

 

I have done some work on the vehicle and finally there are no error codes. I'm not much of an additive person but I did put this in my gas. All the stuff that came out of the exhaust was really something. Exhaust smell clean (if that is possible lol) No visible smoke. Ran like a champ. Now smoke is back and so far traced the under the hood smoke to near the bottom of turbo. Please tell me it's not the head gasket?