Jumpy Car When First Started?

[Spinstorm]

I recently had my car serviced by a volvo dealer to change the cambelt
and do an essential service at around 165,000 miles - it is a 1998 S40
2 Litre.

Anyway a couple of days before I took it to volvo I noticed that when
I started the car up everyday and started driving it seemed to be
stuttering or jumping (im not sure how to describe it) but it just
seemed to jump when I changed gear until the car warmed up.

Now I am no expert on cars but I assumed that may be the spark plugs
(for no reason at all just a random thought) but that whatever it was
Volvo would notice it when they had it for service and would sort it
and indeed if it was spark plugs then change them.

But they didnt change any spark plugs (and maybe they didnt need to)
and I am still having the same problem.

I have no reason to think it is the spark plugs I just have this idea
in my head - if I am right then great but if not what is causing this?
it seems to be worst in lower gears until I get going and then the car
runs smoothly.

Any insight would be appreciated! Thanks.

 

[JM Albuquerque]

I recently had my car serviced by a volvo dealer to change the cambelt
and do an essential service at around 165,000 miles - it is a 1998 S40
2 Litre.

Anyway a couple of days before I took it to volvo I noticed that when
I started the car up everyday and started driving it seemed to be
stuttering or jumping (im not sure how to describe it) but it just
seemed to jump when I changed gear until the car warmed up.

Now I am no expert on cars but I assumed that may be the spark plugs
(for no reason at all just a random thought) but that whatever it was
Volvo would notice it when they had it for service and would sort it
and indeed if it was spark plugs then change them.

But they didnt change any spark plugs (and maybe they didnt need to)
and I am still having the same problem.

I have no reason to think it is the spark plugs I just have this idea
in my head - if I am right then great but if not what is causing this?
it seems to be worst in lower gears until I get going and then the car
runs smoothly.

Any insight would be appreciated! Thanks.

Not spark plugs.
Spark plugs don't miss fire anymore, and even if they fail once
in a while the car won't jump.
My 440 injection jumps due to the clutch, but some good
acceleration fix the problem, up till I burn it. It's a Renault engine
anyway, but a good one.
In your case I bet its a general injection shutdown, due to...
Back to the work shop.

 

[Spinstorm]

Isn't that rather dramatic?

Anyone else got any other ideas?

The car stutters when the engine is cold it seems for like a second
and its ok and it happens when the revs get low and changing gear
helps it.

The engine doesn't make any funny noises it just seems to lose a bit
of power for a second before being ok - mainly its annoying because it
shakes the car though Im very sensative and its not as bad as I make
it sound.

any ideas would be appreciated and if you have any ideas I would
appreciate an explanation of what they mean and what i need to do to
sort it as Im not a mechanic or know anything special about cars.
thanks.

 

[JM Albuquerque]

Isn't that rather dramatic?

Anyone else got any other ideas?

The car stutters when the engine is cold it seems for like a second
and its ok and it happens when the revs get low and changing gear
helps it.

The engine doesn't make any funny noises it just seems to lose a bit
of power for a second before being ok - mainly its annoying because it
shakes the car though Im very sensative and its not as bad as I make
it sound.

It looks like a shutdown, and it can be a fuel shutdown, or and
electrical shutdown.

Look at the ignition coil.
If the ignition coil says Magneti Marelli ...
(only two advice for me, at the third "second shutdown" gone dead).

It could be many things, simple or complicated.
A look at the spark plugs colour could tell something for a start.
Lose connections ?
There are about 10 sensors around that communicate with a computer
that drives the ignition coil and the injectors.