I own a 1987 Audi 4000 CS Quattro. After a fill up the car would not start, fuel pressure to the fuel distributor but not to the fuel rail. I had the fuel pressure regulator replaced and the car starts but now the car takes 8 - 10 seconds to fire as opposed to the formal quick fire. Can the regulator be adjusted? What other possible issues might I be facing.

Thanks

 

a stock FPR cant be adjusted. id have to say either fuel filter, injectors, plugs and/or wires. if it doesnt misfire when its running, rule out plugs/wires

 

If the FPR cannot be adjusted and the car will start laboriously after 1 - 2 minutes now do you think that the plugs could have been fouled from all the dry starting? Is there any connection between the vacuum system because now my doors locks do not work?

I dropped the car off back at the mechanic who 'fixed' the problem but I have had little luck with his mechanics being good or inexpensive.

 

well i know the central locking systems are controlled by a vacuum system, but im almost positive that it has its own vacuum pump seperate from the engines. i doubt its your spark plugs. i would honestly try your fuel filter first. its cheap and more than likely the problem

 

I think Colony is right... i also think that it is not about your fuel pressure regulator but something in your spark plugs.