850 auto problem

Hi all, I have had my L reg 850 around 3 months and considering its age
its been fine.
But occasionally it cuts out on me. Just after I pull onto or drive from a
roundabout I find that the engine has quit and I am coasting.

The sound insulation is so good on these cars that it takes a while to
realise it has happened, I start to put my foot down and nothing, a quick
signal and coast to the roadside is all I can do.
Put in park and it starts up immediately and everything is fine, not
spluttering, no juddering, no smoke, either before it happens or after it
starts, just a smooth instant transition from running to not running.

Has anyone any idea what could be happening. Are there any sensors that
could be cutting it out?
It happens no matter how long it has been running, when cold or after a
good run on the motorway.
It averages out at once a fortnight at the moment. thought I must have had
popped it into neutral the first time it happened but no, it was still in
drive.

Any idea's?

Chris

 

I surmise from your use of certain terms that you're in the UK which
means you experience this problem when turning to the right. No? Do
you also experience this on regular right turns?

You don't say how old your 850 is ( well, actually to you Brits, I
guess "L Reg" means something but in terms I, an American, can
understand, it doesn't convey any useful information).

I would suspect an intermittent ignition wiring fault caused by the
engine moving to the left. A bad motor mount might exacerbate the
problem. If the car is relatively old, a motor mount problem would not
be out of the question.

Chuck Fiedler
Nothing but Volvo since 1974

 

have a waggle of the ignition key whilst you are stationary, engine running
and see if it dies when waggled. worn ignition switches are pretty common on
the 850 (especially when the key bunch is heavy with other keys) and the
symptoms are exactly what you descibe.

Tim..

 

I also have a 1993 (I assume that's what "L reg" indicates) 850 GLT
that used to have the same problem. Turned out to be a faulty
crankshaft sensor - which was duly recorded by the diagnostic unit and
shown as faults 3-1-4 and/or 3-2-4. How about reading the trouble
codes first?

Jarkka

 

In an earlier contribution to this discussion,

Yes, the OP is almost certainly in the UK - both from the reference to 'L
Reg' and to his email address. Roundabouts are driven round in a clockwise
direction in plan view. Negotiating a roundabout first involves a left turn
when joining it, followed by a right-hand arc, followed by a left turn to
leave the roundabout. So, if the engine is loose, it could be swaying about
quite a lot during this time!

The system is different (again!) now - but when that car was new, the
registration number (licence plate if you prefer) carried a prefix letter to
indicate the year of first registration. From memory, 'L' would be 1993/4.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

 

Roger, thanks for the response. After thinking over my response, I'm
afraid I was thinking in terms of the earlier Volvos. The 850s, having
a transverse engine, wouldn't exhibit the phenomeon I suggested.

Someone earlier suggested checking the ignition switch and I would
agree that makes sense. Checking error codes also makes sense.

 

Ok people, some one tell me how to read the codes, where do I find them?
I have never been lucky enough to have a car that had this feature before.
I am slowly driving myself into the 21st century, one car after another.
I am actually a woman and in my youth ( a long time ago) I did actually
train and work as a mechanic, in those days we had mini's, and triumph
heralds, and little Morris minors. Oh how things have changed.
The crankcase sensor was actually my first intuition, so we shall see if
my hunch was right.
Chris


: On Thu, 12 Jul 2007 17:53:02 GMT, "outofthewoods"
:
: >Hi all, I have had my L reg 850 around 3 months and considering its age
: >its been fine.
: >But occasionally it cuts out on me. Just after I pull onto or drive
from a
: >roundabout I find that the engine has quit and I am coasting.
: >
: >The sound insulation is so good on these cars that it takes a while to
: >realise it has happened, I start to put my foot down and nothing, a
quick
: >signal and coast to the roadside is all I can do.
: >Put in park and it starts up immediately and everything is fine, not
: >spluttering, no juddering, no smoke, either before it happens or after
it
: >starts, just a smooth instant transition from running to not running.
: >
: >Has anyone any idea what could be happening. Are there any sensors that
: >could be cutting it out?
: >It happens no matter how long it has been running, when cold or after a
: >good run on the motorway.
: >It averages out at once a fortnight at the moment. thought I must have
had
: >popped it into neutral the first time it happened but no, it was still
in
: >drive.
: >
: >Any idea's?
: >
: >Chris
: >
:
: I also have a 1993 (I assume that's what "L reg" indicates) 850 GLT
: that used to have the same problem. Turned out to be a faulty
: crankshaft sensor - which was duly recorded by the diagnostic unit and
: shown as faults 3-1-4 and/or 3-2-4. How about reading the trouble
: codes first?
:
: Jarkka

 

Modern Volvos (and nearly everything else) have an OBD system of one
kind or another. Generally, they require a reader device and any
modern mechanic should have one and be able to read the codes and
determine the problem.

 

If the vehicle is pre-1995 (which I suppose it is), there's a diagnostic
unit in the engine compartment, beside the washer fluid filler cap. The DU
consists of two smallish black boxes. Lift the covers off the boxes and
you'll find there's a flylead attached to one. Pull the flylead out of the
cover and stick it into one of the sockets listed below. Switch ignition on
and press the little button on the edge of the box for half a second or so;
the LED beside the button will start flashing. Count the flashes; they come
in three groups separated by a couple of seconds or so, making up a
three-digit trouble code such as 3-2-4. Count the flashes. If you get 1-1-1,
no codes have been registered. If you get something else, after each code,
press the button again until you get the same code that you got the first
time.

The systems connected to the sockets are as listed below.
In this case, sockets A6 and A2 are the most interesting ones, but why not
check them all while you're at it...

A1 - Automatic transmission (if present)
A2 - Fuel injection system
A3 - ABS, TRACS (if present)
A6 - Ignition system (I think this applies to 20-valve engines only, i.e.
cars with LH3.2-Jetronic)
A7 - VDO instrument cluster (if present)
B1 - Electronic climate control (if present)
B5 - Air bags (if present)
B6 - Electrically-operated front seats (if present)

http://www.troublecodes.net/Volvo/
lists at least some of the codes. Let us know what you find.