960 Wagon cranks a long time before starting (and getting worse!)

I have a 1992 Volvo 960 (110,000 mi) wagon that seems to take longer
and longer to start. It's been hot and humid here in western PA these
past few weeks and this seems to have exacerbated the problem. It has
always taken a while to start up since I've owned it (almost a year
now), but it has now also started missing as I pull away from the curb
in the morning. Nothing terribly dramatic, but a bit of stumbling
before she'll take off.
While my mechanic was doing some other work, he pulled, inspected and
cleaned the plugs as he was curious about why it took so long to start
up. Of course, he wasn't that curious and when the problem continued,
he didn't look into it.

I have to admit a bit of ignorance in regard to how long it should take
for this car to start; I've only owned small Japanese cars which have
started almost immediately. Is this just a Volvo thing? It takes
about 2.5 to 3 seconds to start up. The battery is less than a year
old.

Thanks,

 

Assuming the plugs and wires are good, how old is the distributor cap,
points and rotor?
My guess is that a delayed start is probably a lack of fuel or fire,
and I'd lean towards fire (spark).
Other than that, if your battery was weak and she was turning slow,
that would do it too. Not sure if the coil might be at play here also.
That's the direction I would pursue first.

Stumbling at the curb might be a dirty throttle body.

 

Sounds like it needs a tune up.

I have to wonder why go the time and trouble to pull the plugs and not
replace them?

(after the tune up)
Fuel (injection) pumps bleed pressure when they get older. No big deal
but it makes starting harder.
As a test:
Instead of grinding the starter until it starts just bump it so the
motor turns a couple revolutions. Release and try it again.
The first bump builds pressure in the rail and (usually) it lites on the
second try. If not, release and try again.
If it's going to fire, it will do so in two or three revolutions. Unlike
carbureted engines, injected motors don't need to spin and spin to lite.

 

Another test is to jumper across the fuel pump relay socket to manually
power up the pump, give it a second or two to pressurize then turn the
key to start, the engine should start almost immediately on these cars.

 

Also check the two ignition amplifiers (each feeds three plugs) and the six
plugtop transformers (each plug has it's own coil). There is an American
vehicle, possibly Ford Bronco and others using the same engine, that has
this arrangement. One plug transformer was misfiring on a Bronco in Spain
and was successfully repaired to give perfect firing once more. It was
having difficulty starting.

All the best, Peter.

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

 

Thanks a bunch for all of your suggestions. I'll have to set aside some
time to get under the hood before my next roadtrip.

I rather enjoy my wagon and would like to keep it in good order for a
while yet. 14 years old and she still has enough guts to haul a load
of railroad ties without much fuss!

Thanks again!