Someone who was on my site sent me this message, can people please help him with what sounds like a matter needing urgent attention -
 even if it has been going on for him for a while!
 thanks -Michael@sydney

 Hi,

 I was wondering if you can please give me some ideas. I have a Volvo
 850, 1994, 75,000 mile, that I service regularly with oil change and e.t.c. Since the last two years I have been experiencing the car suddenly
 stalling with all the lights (engine, oil,battery etc) coming up. The car suddenly dies and feels heavy and uncontrollable. I can however start it
 again in a few minutes. It also happens soon after I have made a left turn.

 This has happened about four times and as recently as today. The Volvo service center in my town cannot find anything wrong. I am really
 afraid to drive my car . One of the times that the car stalled was when I was entering a Freeway ramp. I am afraid that the next time I might not
 be so lucky.

 Any advice will be greatly appreciated,

 Sonal
 Thousand Oaks, California
 --
 Michael @Sydney
 

 Here's my 2 bits on sudden stalling:
 Right after I bought my 850 - that had been standing for almost 6 months,
 it stalled a couple of times - and then the stalling disappeared.
 A week ago, it reappeared. At an intersection while idling -it stalled.
 This happended 4 times more.
 When I bought it - the stalling always happended when I coasted into a red light.
 The day before the latest stalls, I had the radio and cabinlights on all day while cleaning the car. When I later recharged the battery, I found the
 voltage very low. The stalling took place when idling - so it looks like the fuel relay quits when voltage is low - and I had headlights on, fan and
 AC running - while idling (as far as I know, the battery is not charged enough when idling).
 All in all it looks like the fuel relay is sensitive to low voltage, but is designed to survive cranking - after a certain time.
 I took a closer look at the relay - an advanced little german thing with integrated circuits and all.
 Former posts on the Brickboard mentions that a new battery makes the problem disappear
 - others that a new relay (70$) cures it.
 Well - I recharged the battery - knowing that the Chicago rushhours with still standing traffic, idling and heat drains the battery -
 and right now the problem has not reappeared.
 The fuel relay is located behind the fusebox over the torpedo.
 4 Torx screws loosened, the relay is green, marked "103" - and can be easily taken apart for a temporary override to fix the problem.
 Has anyone got the final correct fix for this?
 (like the charging relay may be too slow at kicking in)
 --
 Bo - 1993 850 GLT 137000 miles

Additional correspondence to ozbrick from a 850 owner, November 2001:
 

I recently experienced a stalling problem on my '94 850 would stall under partial acceleration. A few seconds later it would start back up
on its own. The problem was narrowed down to a bad cam position sensor. This was about a month ago and all seems well so far.

Jack
 

Hi,

 I have a 94 850T that has recently decided to have a lot of problems. The one that has me a little
 stumped is this: It starts fine, idles kinda fast for a second or two then drops down to normal, pretty much
 what it has allways done, but then after about 5-10 seconds it starts to run VERY rough and dies. No
 amount of coaxing will keep it going. When I access the fault codes at the DLC, I get nothing in box A
 socket 6, I mean NOTHING. No 1-1-1 "all is well" code,nothing. The LED just stays dark, It doesent even
 light while the button is depressed. I am suspecting the ECU, the Motronic 4.3 fuel and ignition are "tied"
 together from what I understand and in box A socket 2 I get an occasional 3-2-5 fault, "ECU memory
 loss". This may be caused by me occassionally unhooking the battery but I am not clear on that.

 ANY thoughts appreciated.

 -Tracy

Hi again,

 After more screwing around I have noticed that if you really stomp on the throttle as the cars is dying, kind
 of like pumping the accelerator, you can keep it running. Its as if there is no low RPM/idle circuit
 functioning. Also I have been noticing that after the car is started(and it does start right up) it idles really
 fast and SLOWLY drops down to a reasonable idle. Then it goes rough and dies. The fact that the LED
 in the DLC wont even light in socket 6 in box A makes me think that I have a ECU problem. Anyone out
 there a Volvo mech? PLEASE HELP! I love my 850 but it has recently had a series of problems,AC
 clutch,thermostat,warped rotors,even a bad window washer pump,and now this. I want to have my sweet
 running car back.

 -Tracy

 I'm not a Volvo tech but I did have a rough idling problem with my '95 850 turbo a few years back. The
 car would start up and idle very poorly, if I give it anything less than full throttle, the car would sputter and
 stumble and sometimes even die on me. It took the dealership almost a week to finally trace it back to a
 faulty front O2 sensor. It was quite weird at the time because the check engine light never came on so I
 assume no codes were stored and that is why it took the dealership so long to figure it out. You might
 want to check if there are any other codes stored in the A2 socket--this is where a majority of the
 driveability problems relating to emissions will turn up. As for the A6 socket, I'm not too sure on this but I
 think that socket isn't even used.

 Good luck with it.

 People can guess all day here but why? I'd advise taking the car to a dealership where an experienced
 Volvo tech can properly diagnose the real cause.

 I am suprised by your post Lars, asking questions and sharing knowledge is why this message board is
 here. If we all followed your advice this website would not be of much use.

 does it drive, i mean can you engage gear and move the car? is it smooth or stuttering?
 sounds like either fuel or electrical. you checked you sp plugs? my bet is on fuel supply. but you need to
 go thru a whole rigmarole elimination process to determine the exact fault, best go to a volvo indie to get
 help.
 rgds
 jeff
 95 855T5A SAM chip

 Just a thought... possible fuel relay switch?
 They are ~$70.00 US. I would check the archives. I recently printed out some info. on the location of this
 switch for reference. I believe its physically near the fuse box. Sorry, I don't have the copy close to me. It
 may even be in some of the most recent posts. Also, I have heard its a good practice to keep a spare,
 and know where the module is located.

 Kirk

 Hi Tracy - get your battery charger out and try this -
 it is free and can be done overnight while you sleep :) .
 I just shared your problem last week -
 and the immediate solution was recharging the battery.
 even though the battery is strong enough to crank the engine,
 the fuel relay demands a higher voltage, or it shuts off
 when your car is idling (not charging).
 Your low voltage can come from slow moving traffic, lights on and AC running at the same time - this will
 drain the battery.
 Older batteries are not able to stay at a high voltage as long as new -
 a battery is usually "old" in performance after 1 to 2 years - but will function well in mant cars for years
 more.

 Here is my posting from last week,
 it looks at the cause of the problem -
 but noone has this far wanted to verify/ :
 "Here's my 2 bits on sudden stalling:
 Right after I bought my 850 - that had been standing for almost 6 months,
 it stalled a couple of times - and then the stalling disappeared.
 A week ago, it reappeared. At an intersection while idling -it stalled.
 This happended 4 times more.
 When I bought it - the stalling always happended when I coasted into a red light.
 The day before the latest stalls, I had the radio and cabinlights on all day while cleaning the car. When I
 later recharged the battery, I found the voltage very low. The stalling took place when idling - so it looks
 like the fuel relay quits when voltage is low - and I had headlights on, fan and AC running - while idling (as
 far as I know, the battery is not charged enough when idling).
 All in all it looks like the fuel relay is sensitive to low voltage, but is designed to survive cranking - after a
 certain time.
 I took a closer look at the relay - an advanced little german thing with integrated circuits and all.
 Former posts on the Brickboard mentions that a new battery makes the problem disappear
 - others that a new relay (70$) cures it.
 Well - I recharged the battery - knowing that the Chicago rushhours with still standing traffic, idling and
 heat drains the battery -
 and right now the problem has not reappeared.
 The fuel relay is located behind the fusebox over the torpedo.
 4 Torx screws loosened, the relay is green, marked "103" - and can be easily taken apart for a
 temporary override to fix the problem.
 Has anyone got the final correct fix for this?
 (like the charging relay may be too slow at kicking in)

 Try it, take the car for a spin afterwards -
 and when in pile ups - reduce powerdrain by turning off the lights and keep the fan low
 - or put the car in neutral and keep idling at 1500 rpm, where it is sure to charge (a bad solution - only for
 emergensies after a stall)
 Sorry about the language - as a Dane I'm still new to american.
 Hi from Bo

 --
 Bo - 1993 850 GLT 137000 miles

 Try a K&N air filter element.

 I was having strange idle problems
 and hard starting. The K&N cleared
 this right up. Why? Maybe due to
 the increased air flow.

 RD

 Socket 6 on your DLC is not used. It is only used on NON TURBO LH 3.2/EZK cars, 93,94,and some
 very early 95s, USA. The memory loss code is usually conected to battery disconection or battery
 problems. Pump relay is a possible problem. Have seen hose from fuel pump to tank unit come off,
 causing weird problems. I would get a fuel pressure guage and hook it up to see what is going on with
 the fuel pressure.
 --
 bob

 That depends on the questions. There's definately times where boards like this are more useless for
 some questions than others. If you still doubt my opinion, just gander at some of the other guess-me
 answers so far like "maybe this, maybe that, try this, try that...yada, yada" (one can waste alot of
 time/money sometimes quessing that way).
 If some asks a more specific question, surely someone should know but it just doesn't always work and
 there's times when it just makes more sense to have it checked by someone who might spot the problem
 once seeing the car. Just my $.02

Another thread:

  I'm still in the honeymoon phase with my newly bought 94 850. I'm still trying to get the A/C fixed but here is a bigger problem:

  When the A/C guys had my car up on the jack, I saw the vacuum canister sitting loosely at the bottom of the car, just dangling in the engine
  compartment. There is one line with a right elbow that is not plugged into a port. I'm guessing that is a vacuum line for the canister but it
  wouldn't reach anywhere.

  Can you guys tell me where your vacuum canister is mounted and what lines are coming out of it? there aren't any good pix in the Haynes
  manual. There's been three times now that when I'm cruising down the road in neutral (5sp manual) that the engine dies by itself.

  Thx in advance

  The "charcoal" canister that is mounted on the left,(driver's side) front of the car should have two vacuum lines attached to it. The canister is
  mounted with a metal bracket and 10mm long bolt. On the top of the canister there is a marking for either "tank" and / or "engine".

  One vacuum line goes to the intake manifold, the other to the gas tank.
  This could be causing your stalling problem. Also, if the canister is
  just dangling, make sure it isn't broken (cracked from a hit).

  pete

For 4 years our 850 non-turbo wagon has had it's ignition cut out and all the warning lights come on the dash maybe 5 or 6 times. It starts right up immediately fine. It has happened very intermittantly, in cold weather and hot, during warm up and after driving a while. Once I checked the codes and it indicated intermittant cam position sensor failure. But the guy at my local Volvo dealer said he had NEVER sold one, so I left it alone.

But recently I was driving in heavy rain and the engine cut out several times. What was odd was that twice the warning lights came on but the engine did not die. In other cases, the engine died too. Again, it started up again fine. There were no error codes after this most recent episode.

What is this? Another Volvo service guy said it could be the alternator. If the alternator gets doused with water, will it do this? (I did run through big puddles) Is the recent cutting out caused by the same thing as the earlier times? I have replace the cap, rotor, and plugs, but other parts like coil and wires are original. Thanks for any help.
--
George

Also look into vaccuum leaks. An intermittent vaccuum leak can cause a blip in the system that shuts the engine off, while allowing it to start right up again as if nothing had happened.