I have a 1996 850 SE Auto sedan (non turbo).
An issue as of yesterday is that it is starting and stalling either immediately or after a very short distance, dash lights come on but only when engine stops, otherwise no engine light is showing.
Only known issues are these.....
Ignition switch (have to turn it back a bit to get power after starting)
Slight exhaust noise (had warped manifold with two broken studs - only thing I have dealt with so far) mufflers can wait.
And no actual service yet since I have had it (a few months) it had timing belt done last year by previous owner and runs well otherwise.
Before I prod and poke, I wonder if this is an obvious to anyone ??
Electronic or mechanical you reckon? Could be alternator on the way out or a dicky sensor.
Or PCV if it hasn't been done in a while (when it's running, take out the dipstick and see if much steam comes out, can lead to boggy performance/stalling if it's really clogged.
I'd run my eye over the engine bay to make sure all wiring is in order and no vacuum tubes have popped off anywhere first. Could be something simple.
Thanks for responding Dan.
My first thought was electric (I know there are a few sensors etc) as it just cuts out at a turn (or a roundabout) that made me wonder if it is as revs drop ?
It happened a few times last night (that was first time ever) and then today I couldn't get more than a few hundred metres.
I had a look this arvo and did find the skinny black vacuum hose from ''top air filter box - to - 3" air intake tube extension below'' was off.
The small 'right angle' adapter on the intake tubing had perished so I cut some off the hose part above where it leaves the top of the box and adapted it to get that back on the tubing (where the cold/warm intake adjusts) it isn't a tight fit though at either end - how much vacuum would that need ?.
I then ran it idling for 20 minutes and then around the block a few times and was fine - just now went for a run about 6 K's and stalled twice but went again and got me back.
Only other thing I forgot is that it does have a puff o smoke on start or after sitting on idle - light grey-ish in colour AND I did just look and whilst still running after return from the 12 KM drive it does have small amount of same from dipstick (bit dark outside now but seemed same as I see at rear end)
1st places to try are the maf unplug it and.see how it runs, could also be fuel pump.
I have had a bit of a look around the net now and I will look at those next and there is a few chats about throttle body sensor too.....
I can hear the fuel pump when I turn key on.
Also to describe a little better, it always cranks and always fires - just sometimes fires and dies straight away the same way it would if I use the "door locks only" key.
It doesn't yet seem to be a cold start thing, always first occurs when driving and then as I attempt to restart - still always fires but was dying straight away (before reattaching that hose this arvo - tonight's drive it let me restart OK after two attempts and a little wait - just that it happened twice while driving)
I realise its a bit vague without actually ruling out any items first though.
Unplug the MAF as was said above , the IAC valve may need cleaned but check or just replace all vacuum hose with new.
How is the dizzy cap and rotor?
Check the plugs , may be rubbish , only use Volvo ones.
The leads can be worth doing too , again , Volvo 'Bougicord ' ones are best.
Coolant temp sensor?
The flame trap box and hoses may be broken or blocked , likely , they always are ....
Parts cheapest from FCP Euro , Rockauto , PFS in UK , even with postage still cheaper than here.
If any other of the vacuum hoses look perished/crusty, that would be my first stop. Cheap enough to replace all them and they can cause anything from stalling to high idle and everything in between. Being a 1996 model too, you might want to get the OBDII codes read either by a shop or a mate if you have any with an OBDII reader. Might be the quickest way to find a solution.
Cheers for all this
A quick visual inspection today before I got busy with other things and all hoses looked OK but very slight age cracks some of the joiners - everything plugged and not damaged as far as dizzy etc and air filter looks brand new.
It wouldn't start today at first few goes so I unplugged MAF connector and it went fine, untill about 20 minutes later and I turned it off after a drive - wouldn't go again - it took several stop starts to get back home (I even took the Air Idle plug off - no diff)
It felt like it wanted to cool down (maybe a temperature thing as mentioned - should have unplugged the temp sensor as these cars can run run with stuff unplugged I gather - now that's living on the edge LOL) but now each time it won't keep running after initial fire it's kinda like it's starving for fuel with a sputtering end to each fire - so I'm hopeful to get more time over NEXT FEW DAYS OR SO to start closer checking.
Thanks for all the input so far and the cheaper parts source too - these seem to be the most important things to look at.....................
All hoses / vacuum lines and joiners
Idle Air Control and hose (Clean & inspect)
Throttle body (Clean and inspect)
Fuel pressure at fuel rail
Fuel pressure relay
Fuel pressure regulator
Codes (may buy a scanner as will always be handy)
Coolant Temperature senor (and thermostat)
Spark plugs & leads (although I feel they were done with timing belt a about a year ago previous owner)
PCV system piping / flame trap / oil trap ?
EGR Valve / sensor
Oil and filter change
Dan mentioned Alternator - (Voltage regulator ?)
I'll report back when have bought some bits and made some progress : )
Ahh shit, where's my torx set gone !!
No real progress yet BUT.......
(These really are well made cars, other than variances of suppliers and markets the cars were sold in - things seem so well engineered - and I'm certainly learning as I go......)
It was mentioned to unplug the MAF sensor so I tried and thought I had but have found that as it's a 10 Valve engine it therefore does NOT have a MAF sensor - instead it does have an Air Temp sensor in the top of the Air Filter Box and a MAP sensor (Manifold Air Pressure) near the radiator.
'DOHC' on the top cover means the 10 Valve engine (B5202S)
The Air temp sensor is smaller and the working end of it looks more like a resistor soldered to two prongs (it is only rubber push mounted too).
So far only other thing is that fuel pressure is good and all hoses and connectors are good too - Oh and getting parts prices etc before I get hold of a code scanner and also some more appropriate tools ; )
Code scanners can be your android phone loaded with Torque app and a very cheap OBD Bluetooth sender unit.
Or a hand held obd scanner for less than $30 delivered from eBay , same as what Supercheap charge $100+
Use MAF cleaner on the air temp sensor??
Okeeey - just thought I'd unplug the MAP (has a vacuum line from manifold) before I go out for the day - made it worse, now has engine light - also the fans came on after I took the key out and walked away from the car !! plugged it back and tried but def no start now - still only runs for a second then dies so hopefully if any codes show that will help - thanks for the info on scanner, will look on ebay later : )
Have you checked the fuel pump relay when it cuts out? My old 850 had a similar issue when it got hot, the relay would overheat and stop working. The relay was getting so hot you couldn't hold it. When replaced with a new one everything was fine.
Sorry I didn't get back here sooner - (forgot once fixed), thanks Brock - you won !! Fuel pump relay (Under fuse box) $140 OEM - the capacitors dry out in these and is extremely common with age of car - it's intermittent untill they stop altogether.