1994 940 B230FB misfires like morse code

[Speedmonkey]

Hi guys,

Groundwires, relays, sparkplug cables are all just fine. Checked them over and over again. But....it looks like with the meths in my fuel the misfires are becoming worse...You can feel the car hesitate more during highway cruising...

So I guess the next step is to tap some fuel from the injector rail to see if i can detect water...That should be great to find some...Also because two specialists checked the car and couldn't find anything wrong....

I'll keep you posted!

[Speedmonkey]

Hi guys!

Finally some progress I hope....Tapped 3/4 of a litre fuel from the return line at the pressure regulator. Let that sit for two ours and ended up with half a thee spoon of water on the bottom of the bottle....

Maybe that caused the misfires...Now the next thing is: How do I get the water out of the tank completely?

[Laird Scooby]

Originally Posted by Speedmonkey

Hi guys!

Finally some progress I hope....Tapped 3/4 of a litre fuel from the return line at the pressure regulator. Let that sit for two ours and ended up with half a thee spoon of water on the bottom of the bottle....

Maybe that caused the misfires...Now the next thing is: How do I get the water out of the tank completely?

If that amount of water is present in the fuel lines then firstly that confirms the fault and secondly, run the tank down as far as possible, add another litre of meths and a few (like 5 NOT 50) litres of fuel.

You could try siphoning some of the good fuel off and adding more meths to the tank now, that might work but i think you'll have to just keep adding the meths to a very low tank and only a few litres of petrol with each litre of meths.

[Laney760]

Originally Posted by Speedmonkey

Hi guys!

Finally some progress I hope....Tapped 3/4 of a litre fuel from the return line at the pressure regulator. Let that sit for two ours and ended up with half a thee spoon of water on the bottom of the bottle....

Maybe that caused the misfires...Now the next thing is: How do I get the water out of the tank completely?

We've already told you! :-) Meths! Put in the meths when you don't have a lot of fuel in the tank, repeat until misfire totally dissapears. Thats what I did

However, as I said, I'm no mechanic but I've read that if its been in the system for a while it supposedly rusts some steel parts, take a look at the link I posted

EDIT - Dave beat me to it :-)

[Dirty Rooster]

This worries me after all the good advice ;

Originally Posted by Speedmonkey

The first liter is in, together with 50 liters of fuel...

[Speedmonkey]

I can imagine that it worries you...but I was being cautious...Better safe than sorry, I've got only one Volvo...

No progress on emptying the fuel tank though...

[Laney760]

Originally Posted by Speedmonkey

I can imagine that it worries you...but I was being cautious...Better safe than sorry, I've got only one Volvo...

No progress on emptying the fuel tank though...

As said, if you add the meths to a small amount of fuel in the tank, you'll get rid of it quicker and you need to get rid of it quickly, read the link, because the water that has travelled around in the system before it sank to the bottom of the tank rots steel components, its maybe already damaged your fuel injectors

It was January 2016 I used the meths, no changes to my engine for the worse http://www.volvoforums.org.uk/showthread.php?t=241361

Originally Posted by Clan

I remember volvo recommending in one of the old green manuals white spirit to do the same job , i.e. emulsify the water to allow it to go through the system and be burned .

[Speedmonkey]

Hi Guys,

Sorry it took so long for an update, the weather was good so I used the motorcycle more then the Volvo so it took a while to empty the tank.

Meanwhile I had already tried 30 Litres of fuel with 3 Litres of alcohol, with no result...So today I drained the tank with the fuel pump. Disconnected the line at the pump and short circuit the relay...A milky mixture came out. Put new fresh fuel in but also with no result...

So the next step is: Drain the tank again. Flush with 2x 5 Litres of alcohol. Remove fuel filter. Blow out all fuel lines. Place new fuel filter...Then it must me solved...

I'll update you guys with the results when I found the time to flush the system...

[mocambique-amazone]

Hey Speedmonkey, did you solve the problem?
Regards, Kay