Ongoing no start 940 and other woes!

[vickyg]

Some of my 940 (93) woes….and a car that no longer starts and has been SORN’d since Xmas.

- Car always had too slow idle and would stall or struggle left idling without extra revs, I never found a solution.

- Speedo only works after about 10-15 mins driving then works perfectly!

- Sunroof leaking, door channels are clear. Think the metal frame is bent so the water isn’t getting to the channels.

- Heater control too stiff to work via dash control but heater works if you manually turn in the footwell. No leaks at the moment…would love a new valve but missed the last one on Ebay that went for £80.

- Car seems to be drawing amps/power all the time, when parked and ignition off. About 0.25A which is enough to flatten the battery without regular use. I leave it disconnected now.

- At Xmas we went to move to move it, started, failed and never started again. Have had no time to investigate any of this but have been getting the spanners out the last few days.

Have spark
New battery, new plugs
New crank sensor
¾ tank fuel
Both pumps spin (Bosch not regina)
New pressure regulator ordered.
Fuel pump relay works as it should but we don’t seem to have fuel to the engine. Will attempt to start with a squirt of brake cleaner.

Today I’m aiming to test for clogged fuel filter and change the filter. Tried last night but could not get it off! It’s in cradle under the car, 3 x 13mm bolts on the cradle which houses the pump and filter. 2 x 10mm bolts seem to hold these to the cradle, one spins and the other isn’t releasing the strap clamp. Maybe I’m missing something.

Oh and the handbrake cable is snapped but it's an auto and I don't care for the moment lol.

Any guidance would be very welcome. It's gone from flying through an MOT 18 mths ago to all sorts of trouble, lovely drive when it works!

[Forrest]

You would do best to narrow the problem down to fuel or ignition before throwing parts at it.

Are you getting fuel pressure at the rail? If there is a schrader valve underneath the rail between 1 and 2 injectors measuring the fuel pressure is easy with a cheap fuel pressure gauge. Get one with a flexible hose that will be suited to the clearance available.

The petrol may have deteriorated if the car has been standing a long time. Standard unleaded contains ethanol (because eco-morons think green-washing transport is a good use of the world’s agricultural resources) and this alcohol both oxidizes and absorbs water giving it a usable shelf life of about three months.

I found a useful additional test of the fuel system was to remove the short piece of rubber hose in the fuel return line after the pressure regulator and attach a longer piece that you can route into an empty jerry can. Not only does this help, in conjunction with a pressure gauge, to prove the pressure regulator it also enables you to check the state of the fuel getting to the engine without having to dismantle any high-pressure unions.

That cradle under the car it a horrible thing. I used an impact wrench on the bolts and was able to dismantle mine ok. But I had trouble with the banjo connectors and broke the fragile, short hard-plastic fuel line. You will need replacement crush washers. See my thread from a few years ago for details of part numbers and issues with these.

https://www.volvoforums.org.uk/showthread.php?t=287217

[Forrest]

Pictures of my efforts in case they are of any help.

[TonyS9]

Sun roof leaking

Is it a glass or metal type. The glass type can rust where seal presses on, it's not galvanized like the rest of the car. A good bodge is to seal the glass on the top between the seal and the glass, just a small bead if black silicone.

In my case the water made its way around the inside of the seal and dropped into the slider channel which isn't drained.

Also worth pouring some water into the drain and checking the drain is working.

[vickyg]

Have found far worse cause, fuel tank full of water. The drain in the filler was blocked and we've had serious rain. Can I safely use the pump to drain the tank into a bucket? I hope this hasn't written off the engine 😭

[vickyg]

Totally mystified, pulled a hose and so far nearly 15 litres of water. Find it hard to believe this got in via the filler cap in the rain. Sabotage?

[Laird Scooby]

Once you've got the tank empty (you can use the pump to drain the tank if you either link the relay out or unplug the pump in the luggage are and feed it with a spare battery but make sure you're not feeding the sender unit with 12V! ), fill it with 4 gallons of fresh fuel and 2L of meths :

https://www.toolstation.com/methylated-spirit/p99550

That's the cheapest way to buy that volume of meths - any less in 4 gallons (18L) won't be enough and more will be a waste but it will emulsify any moisture still in the tank after draining so it can be burned by the engine.
Once you've got it running, add about 50ml of synthetic ATF to the fuel tank (or 300ml if you fill the tank) to lube the pumps, injectors etc and help derust the metal parts in them and revive the rubber seals. It will also help clean the injectors.

[vickyg]

Have been draining and eventually pure petrol came out. Do you think I should ditch all the fuel even when in a jar no water to be seen?

[vickyg]

It would seem that a clogged drain on the fuel filler rubber boot has allowed huge amounts of rain to overflow into the cap. Is that possible? I've not found anyone else reporting the same. Compounded by a roof rack blocking the gutter so all rain ran down the window toward the flap 😬😬😬

[Laird Scooby]

Originally Posted by vickyg

Have been draining and eventually pure petrol came out. Do you think I should ditch all the fuel even when in a jar no water to be seen?

If you've got it down so that only fuel is coming out, add some meths to the tank to get any moisture that might still be lurking in the system rather than draining it.

That drain just inside the fuel flap can be easily cleaned using either a length of thick strimmer line or a long cable tie just narrow enough to fit inside it. I keep one in mine with the end folded over so it sits with a kink in it so it doesn't fall all the way down the drain.

Usually it only blocks towards the top so as long as you clear that, you should be ok.

Might pay to get a replacement fuel cap with a better seal on it as well.