911 2

my 1991 3.3 turbo 2 has recently started to carry on running for a few seconds even after the ignition has been switched has anyone experienced this and any idea whats causing this

duxducis

Your fuel pressure is higher than factory seting

Sameer

Hang on, I thought this is a norm for the factory cars to prevent to let the engine/turbo cool down before turning it off right away?

Miles965uk

no there is no function like this on our cars.... its happned to my old turbo once but never found out what exactly as it didnt happen again.

Youcef

I have read that the ignition stays on for 5 secs after the engine is shutdown, this operation is controlled by the ignition shut off delay relay in the rear LHS of engine bay. This relay allows combustion of unspent fuel injected after engine shutdown.

Sameer

Yes I remember reading this somewhere, however my car does'nt do this. I do plan on getting a turbo timer.

duxducis

That is right.
So as I sad you may have higher fuel pressure than stock. What happens?
There is unspent fuel injected and that fuel must be burnt.
I have increased fuel pressure and I have the same problem. I had not had that problem before I raised fuel pressure.
I think that this is not in any correlation with engine/turbo cooldown.

911 2

i was told the timing is out can this be adjusted if so how
how is the fuel pressure adjusted and why would it be increased as i only have a performance exhaust 1 bar spring and my car only gave me 16 to the gallon on along run at around 80mph

duxducis

Well I am not a mechanic. I have just told one of the possible reasons for your problem.
Maybe it is something totaly diferent with your car.