Periodic Difficulty Starting

[BoArl]

Hey Bora-enthuitiasts
I bought an 1999 Bora 1.6 which has had some problems starting periodically. It will start after some difficulty but when it does, it will run badly. My brother is a mechanic and says it is as if, it's not getting enough gasoline. We trying checking the fuel pressure in the fuel lines, but the pressure seems fine. It usually happens when it has been turned off for some hours usually overnight. It will not accelerate properly and 'chuck along' and basically run like the speeder isn't responding and the engine isn't getting all it needs or maybe taking in air.
When we plugged in an error coder, the errors (after clearing first) that came back again were -
00668, 01331, 01332
The start plugs have been changed.
Thanks.

[Crasher]

If 00668 came straight back you need to make sure the battery is healthy, modern engines hate low voltage.

[FrenchAudi]

If your battery voltage is OK both at the battery terminals and at the ECU power supply connector (you'll need a wiring diagram to get the pin number), here is an easy check which could be helpful.

Pull off the vacuum hose between the inlet manifold and the fuel pressure regulator (FPR) after the car has stood overnight, before trying to start it, and check for any petrol inside the hose.

I had similar starting problems with two cars which were due to a very small leak through the FPR diaphragm, probably due to the ethanol in the petrol here in France causing the diaphragm to deteriorate.

This allowed fuel to leak through the diaphragm into the inlet manifold when the car was standing. The slight richening of the mixture made no difference once the engine was running, but the amount accumulated in the manifold overnight made the mixture too rich for starting, especially in the summer.

There was a small amount of petrol in the hose, and I proved that to be the problem by disconnecting it at the FPR and plugging it overnight.

Another reason for difficult starting due to an over-rich mixture, on another car, was a faulty water temperature sender - the one for the ECU, not for the gauge on the dashboard.
This was indicating that the engine was very cold, resulting in a rich starting mixture.

[Crasher]

I have only seen that diaphragm failure, not long ago on a Corrado VR6 that had come out of a ten year sleep and been filled with E5 fuel; it had me pulling my hair out for a few days.

[FrenchAudi]

E5 has up to 5% ethanol. In France our 95 octane petrol has 10% ethanol and Denmark can have up to 10% ethanol.

[Crasher]

They keep threatening us with E10 and we resisted, now the pillock in charge wants to ban it outright spending Billions on a technology that not everyone wants, instead of using the fairy fart green electricity that will power this “green revolution” to produce synthetic E fuel which can be distributed and used using the technology we have.