Fuel Pump - Ignition Switch and Brakes

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Apple Computer

('81 245, Auto Trans, K - Jet) I am pretty sure this is what is
happening. The first time I turn the ignition switch on the result is
most normal stuff but when I when I turn it off, then back on, the tank
fuel pump buzzes. Therefore; if I first twist the key on, then crank
the engine, it turns over several times before it fires, but if I
switch it on, then off, then back on, and crank it over, the engine
fires almost instantly. How can this be? In my former MG, Jag, or
Lotus I would not have thought twice about this and assumed it was
supposed to be that way, but I can't think of any reason for this
behavior to exist, so I am wondering why a Volvo does it.

Also, if I drive a while, especially uphill 20 miles for an elevation
gain of 4300 feet and then leave the car for a few hours I will
experience a long cranking time upon restart. It might be related to
the engine getting warmer than usual, not sure. Perhaps the heat
pushes the fuel back down the fuel line?

I was parked on a hill at a stop light and became concerned as the
brake pedal gradually went all the way to the floor. I just had the
brakes serviced by a reputable place (a former employee previously
owned my car) and the master cylinder was replaced so I was suprised.
The calipers are also pretty new and the car does not drop fluids
(Since owning the aforementioned MG, Jag and Lotus I have grown
accustomed to actually having to raise the hood to check if the car has
fluids, sort of a pain.) After some testing it seems like I may not
actually be losing brake pressure. The brakes hold, but the pedal just
sinks. Is this possible? Is it the booster?
 
Apple Computer said:
('81 245, Auto Trans, K - Jet) I am pretty sure this is what is
happening. The first time I turn the ignition switch on the result is
most normal stuff but when I when I turn it off, then back on, the tank
fuel pump buzzes. Therefore; if I first twist the key on, then crank the
engine, it turns over several times before it fires, but if I switch it
on, then off, then back on, and crank it over, the engine fires almost
instantly. How can this be? In my former MG, Jag, or Lotus I would not
have thought twice about this and assumed it was supposed to be that way,
but I can't think of any reason for this behavior to exist, so I am
wondering why a Volvo does it.

Most injected cars will do that if the fuel pressure in the injector rails
isn't holding when the car is off. In fact, that is the shade tree test for
loss of fuel pressure, and the first suspect is the check valve at the fuel
pump. After that the injectors are the second suspect. A bottle of injector
cleaner in the tank is worth a try (cheap and easy, might work) but after
that you have to decide whether you want to pursue it.
Also, if I drive a while, especially uphill 20 miles for an elevation gain
of 4300 feet and then leave the car for a few hours I will experience a
long cranking time upon restart. It might be related to the engine
getting warmer than usual, not sure. Perhaps the heat pushes the fuel
back down the fuel line?

I was parked on a hill at a stop light and became concerned as the brake
pedal gradually went all the way to the floor. I just had the brakes
serviced by a reputable place (a former employee previously owned my car)
and the master cylinder was replaced so I was suprised. The calipers are
also pretty new and the car does not drop fluids (Since owning the
aforementioned MG, Jag and Lotus I have grown accustomed to actually
having to raise the hood to check if the car has fluids, sort of a pain.)
After some testing it seems like I may not actually be losing brake
pressure. The brakes hold, but the pedal just sinks. Is this possible?
Is it the booster?

Not the booster - those are classic master cylinder symptoms. The new one
must have a nicked seal... it happens.

Mike
 
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