1996 850 2.5 20v. Car stopped and will not start. Fuel prob.

wingchun · Post by **wingchun** » 22 Sep 2007, 07:09

Good morning everyone.
My car has just developed a problem that I am hoping one of you good people can help me with.
I parked my car at the shops and when I came out it refused to start forcing me to have it towed home.
Previous to parking, the car was running perfectly and has full Volvo service history. Half a mile before I parked, the petrol warning light came on. I know the car then has about 40 miles left in it. Just incase, I put my reserve gallon in the tank. The tank now registers about 1/8 full. Well above the red line. The petrol light now stays on. If I turn the engine over, it will run for about 3 seconds and then cut out. I took the petrol pipe off the injection system and turned over the engine. Each time I turn it over, only an egg cup full will be injected into the pot. I can leave the ignition on and no more petrol will come out unless I switch off and then on again.
Whilest doing some testing with the ignition on, I noticed a buzzing noise coming from what Haynes manual describes as the idle air control valve. Placing my ear on it, the noise it quite loud. As this is an electrical unit, can it be telling the ECU the wrong information and it shutting the petrol pump down, or do you think there is other problem?
By the way, I live in the UK just incase we have fitments you do not have in the USA.
I do hope someone can help as I am lost without my car!!
Thanking you all in advance.
Terry.

Post by **MadeInJapan** » 22 Sep 2007, 08:24

Terry, the Idle Air Control (IAC) sometimes buzzes loudly and that's fairly normal....I would not start there with my diagnostics. You were low on gas to begin with....a good possibility is that your gas filter or fuel filter (proper name) sucked in gunk from you gas tank. It it hasn't been changed out recently, I would do that and see how she goes. Seems a lot of people have been running into sudden "no start" situations with their Volvo's this summer. The #1 culprit has been a bad fuel pump (do you hear the pump begin with you put your ignition key in position 2?) and #2 culprit is a failing fuel pump relay. Check these if the fuel filter exchange doesn't do the trick. The lack of fuel at the fuel rail is a sure-tell sign and once again, nothing or very little to do with the IAC.

Post by **Ozark Lee** » 22 Sep 2007, 08:46

You have a number of things in motion all at once so lets try to narrow them down.

From what you describe on the fuel flow it is obviously to low.

You have either a bad fuel pump relay, a bad fuel pump, or a bad fuel filter.

Running the car low on petrol is a bad thing to do as being bathed in the fuel actually cools the fuel pump. Running it very low on petrol also causes all of the accumulated dirt to get sucked through the system.

So let's start by eliminating the fuel pump relay. In your central electrical unit (fuse box) is relay 103, that is your fuel pump relay. In order to access it you will need to remove the cover of the fuse box which is held in place with 4 torx screws. Once you remove the cover, remove relay 103 and look at the bottom of it. There are 4 pins and molded into the plastic next to the pins you should see the numbers 31, 31b, 87, and 15.

Make a jumper wire and plug it into the sockets associated with pins 15 and 87. This should turn on the fuel pump and, if that is the only problem, the car should start and run just fine. You can either replace the relay or rebuild it. Check the repair database for the rebuilding instructions if you know how to solder connections.

Assuming that the relay checks out OK and the car will not run go ahead and replace the fule pump relay and button the fuse box cover back up. The next step is to check the fuel filter. Remove the filter and try to blow through it. It should have some resistance but not much. If you cannot blow through it, replace it and try to start the car again.

If it still will not start we are left with the fuel pump itself. There is a filter on the pickup on the fuel pump that can become clogged but it is not nearly as fine as the fuel filter itself and they only clog up with large pieces of debris.

I would tell you how to get to the fuel pump but on a British car I'm not sure. On a North American car it is accessed by lifting the carpet behind the passenger's side seat. For sure its cover is behind one of the rear seats on your car but I cannot tell you with certainty which seat it is behind.

If it comes down to a bad fuel pump you can replace it with a complete assembly from the Volvo dealership which is quite quick and easy, albeit expensive, or just replace the pump unit itself into the cartridge. Walbro makes a replacement that works very well but it is noisy and I also believe that Bosch makes a replacement. The replacement pump units are typically a mail order item here in the states but you might have better luck at locating one in the UK at an auto parts store.

The only other thing that bothers me is the petrol you added to the tank. How old was it? I don't know about the European blends but the gasoline here in the U.S. is junk after about 6 months.

Good luck, let us know what you find.

...Lee

wingchun · Post by **wingchun** » 22 Sep 2007, 11:13

Madein Japan and Ozak Lee, You are brilliant!! I owe you a big thank you.
I checked out the relay as Ozak said by jumping terminals 15 and 87 and the car started! Put the relay back and tried again, it did not run. Removed it again and repaced the wire and everything was fine. Obviously the relay has packed up. I will be down to the accessory shop tomorrow to see if they have one.
Point taken though about being low on fuel, don.t usually let it go lower than 1/8 tank but just finished a journey and I thought a trip tp the shop, a matter of about 600 yards away would be ok.
Incidently, many people here DO run their cars to the last drop of petrol as it is so expensive, fuel at the moment is 96pence per litre, nearly

Post by **MadeInJapan** » 22 Sep 2007, 12:33

Terry, if they don't have the relay, there's a good write-up in the data base section on how to open it and solder out and in the offending parts. If you are savvy at soldering and have an electronic parts store accessible to you, it might be worth considering.