Car is a 94' 850 Turbo sedan, w/ 135K Miles. Engine fires fine in the summer/spring/fall months, but with temperatures slowly dropping into the 30's it is having the same problems it had last winter. The engine turns over, but will not catch. It takes several tries, this morning it was at least 10 times, turning the ingnition on and off. The weird thing is that this only happens when the outside temperatures drop. I've already had the fuel pump relay replaced, and I'm sure fuel pump pressure is good because car starts fine when the outside temp is comfortable....ie: 60 degrees and up. Can cold weather adversely affect the pump? Any suggestions on what esle it could be? Wish I could park in a garage!!!

 

Wow! Just joined the forum for the same problem. Cold temperatures around 35 degrees, hit the ignition, engine fires up like clock work. About 2 seconds later it seems to run out of fuel. This process takes about ten cycles before it runs like nothing has happened. I have changed the fuel filter and even removed the throttle body and cleaned all the carbon out.I thought I had it solved two weeks ago when we had our first snap of cool temps, guess not. Fuel pressure is perfect, I am thinking that a relay is the culprit. Picked up a supposed factory service disc on ebay, but turned out to be a Mitchell copy. I will let you know.

 

I know how you feel!!! I had the relay replaced last winter, it did not change anything for me, but it is said that could solve our problem, it is very simple to do. Please do keep me posted on what you find, this problem is making me late for work, and it is only going to start getting colder.

 

Have you both checked spark and fuel?

 

I had the car serviced at the local dealer about 6 months ago. No spark problems , and no reports of fuel injection problems.

 

Same here,

When it is cold, there is a buzzing like noise (prob around the relay/fuse box) then the engine turns over and even if it starts, it dies out.
Someone here must have figured out the solution.

-

 

Does the buzzing stop after a second or two or is it persistant? My 850 makes a buzzing like noise but it's the ABS system going through a self test.

Alrighty... how was the weather 6th months ago? If it was warmer then the problem might not have manifested it self and wouldn't have been detected.

 

The buzzing noise is more than likely the electric fuel pump being on. - AB

 

Wouldn't you hear that from the rear as it's the pump is in the tank? Although I suppose you could hear the fuel as the system pressurizes.

 

You hear it in the engine bay as well. Open the hood and have someone turn the ignition to 'on'. You will hear the constant buzz of the pump. - AB

 

that almost sounds like the fuel line may be freezing maybe, enough fuel in the rail to start it but it starves itself of fuel

It's probably not that cold for that problem but it kinda sounds like it might happen

 

Dear All,

Greetings from Chicagoland.

I'm sorry to hear your problems, car problems are undoubtedly irritating.

Your car is missing one or more of the following 3 elements:
1. Good compression
2. Good spark
3. Good fuel supply

Or may have electrical/electronic component problems (pain).

Anyway, before blaming more complicated components, have you all checked the basics? 850 is getting old, even the newest ('97 model) is now about 9 years old, and there are items that 95% people neglect. Here are some:

1. Battery & Alternator
If the battery is weak, the engine wouldn't have enough "spin" to initiate combustion. And if the alternator is about to go to heaven, the engine might stall (and never start again). On 850, when the alternator is about to die, many dash warning indicators flash like crazy and the electrical systems begin to turn off less important systems first (e.g., stereo, climate control, then the ignition, etc...). If your battery is more than 3-4 years old, replace it without questioning. I use Interstate Battery for its quality, warranty & free jump start service. I wouldn't buy cheap batteries from franchise stores, because their batteries might have been on the shelf for too long, and the electrolyte (battery acid) level might be too low. If you are unsure about how to test your battery, take your car to a reputable shop and tell them you want to have the following tests/checks done:
1. Voltage test
2. Specific Gravity test
3. Load test (the most accurate method of testing a battery)

Whenever you go to a shop, make sure to talk/act like you know very well what you're talking about.

If your car is over 10 years old or has accumulated over 100,000, and still has the original alternator, replace it without even thinking. If you don't, you'll get stranded at the worst moment (it happened to me). Buy a new/rebuilt alternator with lifetime warranty, preferably a Bosch (OEM).


2. Spark Plugs
When was the last time they were replaced (and are you sure they were replaced? )? And do you know what kind of plugs have been installed (genuine Volvo, iridium-tip, platinum-tip, etc...)? I use Bosch twin platinum and seem to work fine with B5234T. If you know how, remove one or two plugs and see if they are in good condition. Replacement intervals are different for different types of plugs.


3. Spark Plug Wire (High Tension Cord)
This item is often neglected. If this one is bad, your new plugs won't do you much good, as voltage cannot reach the plugs. If your car still have the original wires or have accumulated over 70,000 miles, replace them without even doubting.


4. Distributor Rotor & Cap
Another neglected item. Replacement interval is pretty much the same as the spark plug wires. If they are bad, voltage cannot reach the plugs.


5. Air Filter
On rare occasions, air filter may play tricks according to ambient temperature. When you replace it, use Mann (OEM) filter, rather than some cheap filter.


6. Fuel Filter:
This item actually needs to be replaced much sooner than the owner's manual calls for. I would replace it every 3 years/30,000 miles.
However, this item may not be the culprit for your problem, as someone noted that he/she replaced it recently.


7. Clogged Injectors:
Even if there is sufficient fuel pressure, the injector might be clogged, though this does not happen frequently.


8. Water in the Fuel Tank:
You could try putting a bottle of water remover (isopropyl alcohol).


9. Old Coolant (antifreeze):
May be starting to freeze and putting a strain on water pump? Probably not.


10. Engine Sensor (s):
Is the Check Engine Light on? If it is, have a visit to Volvo dealer. (my local Volvo dealer wants $100 just retrieving the codes).


11. Vacuum Leak:
Check for loose/broken connections or cuts/splits around vacuum lines, including intercooler lines.


If above items are good, then you might want to visit your local Volvo dealer or a shop that specializes in Swedish cars only.

Without actually looking at your car, it is difficult to tell what might be wrong.

Good luck and please inform us of progress.

Best regards,


JPN

 

Some good news.
After cleaning the throttle body to no resolve I went for the idle air control valve. I was carboned up . It was sluggish to move while rotating from clockwise/counter. Cleaned that up with throttle body cleaner. The IAC reacts faster but no solution in the morning.That day I removed the fuel pump relay, #15 terminal base was dark brown, pulled the cover off to reveal the dark roasted interior. That night I hooked up a fuel pressure gauge, timing light to the coil wire to the dist. It was a nice crisp 29 degrees that morning, the key goes into position #2, the fuel pressure pops to spec. Turned the ignition and the car fires up, the fuel pressure drops like my 401k.Replaced the relay and all is right inthe world in the morning, fires right up and runs. I also measured amp draw at the pump at 3.8amps.The relay powers up on position 2, shuts down until ignition is validated and then restarts. My advise is to remove the fuel pump relay, inspect the #15 terminal and replace if the board is dark at that terminal. Good luck, let me know.

 

Looking at your original message, you had replaced the relay. If your pump is failing it will draw more amps as it ages. Sometimes the armature on the pump can have a dead spot on the windings.There are various DVOM's that have amp probes that are inductive, to measure draw. I don't know how much you want to spend, but these are usefull tools. Fluke is the manufacturer that I use. Amp draw from 6 on up is a key indication your pump is failing.