940 B200FT boost problem.

Hi. I have upped the boost on my turbo now sometimes I
get a 'kick' like taking your foot off and on the throttle.
I believe this is caused by the 'boost control switch'
shutting down the fuel pump.
I'm told that it is adjustable.

It is on the curcuit diagram but I can't find the thing
on the car!
Some people have said that it near the pedals on the
boost guage pipe, on my car it isn't.
Does anyone know where it is located?

 

Hi Clive, if you want to sort out if the fuel pump is shutting off, why
don't you put a TEMPORARY jumper on the fuse box to feed power directly to
the pump? and give it a quick try? Please, do not leave the jumper in
place, since if you get into an accident, the pump would continue to run,
possibly spilling fuel from broken gas lines, etc..

 

Hi. Thanks, I,m thinking of trying that. I need to find the pump relay
(funny, I think I feel
a familiar scenario here)!!!!

The pump relay is a dual relay involved with the injectors too so I will
have to think about it.
I think the ECU shuts down the injectors too. I'll test it with a fixed
supply to the pump first.

Many thanks, Clive.

 

It might be like the overboost switch on my turbodiesel. It is a large round
aluminium thing fed from the inlet manifold to it's centre with a two pin
connector attached to it for the electrical feed to the car's circuits. I
don't know how it would work on my car but it is at the top of the lefthand
strut tower. It is basically similar to an aneroid switch.

All the best, Peter.

700/900/90 Register Keeper,
Volvo Owners Club (UK).