1999 S70 NA Hard Starting after fill-up

kumulipo · Post by **kumulipo** » 01 Oct 2018, 19:33

My 1999 s70 n/a has a hard time starting after a fillup, either automatically by the pump, or manually before the tank is full.
Tank is NOT topped off.
Engine will start but must maintain revs 3000+ to run.
Once underway, no problems.
Your thoughts, please.

Post by **misha** » 02 Oct 2018, 03:48

You are getting raw fuel into intake through carcoal canister.
It could be because of tank ventilation system failure.
If it does that always it would be fuel pressure regulator leaking fuel through vacuum line.

Post by **FlyingVolvo** » 02 Oct 2018, 05:34

Any codes that are coming up?

Post by **abscate** » 02 Oct 2018, 06:29

No FPR on a 1999 with ME7 - but the overloaded EVAP canister is almost certainly it.

It moved to the rear passenger floor area, just in front of tire, in late 1998

Added year model to title per forum rules

Post by **misha** » 02 Oct 2018, 06:44

abscate wrote: 02 Oct 2018, 06:29 No FPR on a 1999 with ME7 ...

Not even integrated in fuel pump housing/assembly?

Post by **abscate** » 02 Oct 2018, 07:19

YEs, fuel pressure is regulated there, but without a vacuum line. It is electronically regulated by feedback from the fuel pressure sensor. I dont think that will cause the symptoms reported here.

Post by **misha** » 02 Oct 2018, 07:29

P2 models have the same set up too...at least early ones...2000-2002.

Post by **abscate** » 02 Oct 2018, 07:40

misha wrote: 02 Oct 2018, 07:29 P2 models have the same set up too...at least early ones...2000-2002.

I think it is

1992-1998 P80 Vacuum operated FPR - some on fuel rail, some on power steering rack (years/models?)

199-2001 Bastard FPR electronically regulated, fuel pump relay in fusebox, fuel pressure sensor ?

2002-2008 relay on CEM, CEM drives PEM with a signal, PEM drives fuel pump with another signal - fuel pressure measured on rail

kumulipo · Post by **kumulipo** » 02 Oct 2018, 12:31

Thanks for all your help.
Will post codes next time it happens.
I'm remembering P0405. That's not reliable.
So my repair would be the carbon cannister plus associated hosing? Plus checking the fuel rail situation?
Between fillups it starts easily.
Thanks again!

Post by **misha** » 02 Oct 2018, 15:34

You must find the reason why carbon canister is flooding...not replacing it.
Doing that you will not solve nothing.