1994 940 B230FB misfires like morse code

[Laney760]

Speedmonkey, if you have a full tank of fuel with water in it then it will take a while before the alcohol will combine with the water and burn off. I had to put two lots of meths in for total elimination of water and cessation of the misfiring. That was starting off with just a bit of fuel, not a full tank

[Laird Scooby]

Originally Posted by Laney760

Speedmonkey, if you have a full tank of fuel with water in it then it will take a while before the alcohol will combine with the water and burn off. I had to put two lots of meths in for total elimination of water and cessation of the misfiring. That was starting off with just a bit of fuel, not a full tank

That's exactly what i've been saying in different words, perhaps something is getting lost in the translation?

[Speedmonkey]

Hi Guys,

The empty tank light was on when I put a liter of that purple bbq stuff in...I see now that it contains generally 10% water hahahaha...

I'll get some denaturalised alcohol with NO water and try again....hahaha

First have to empty the tank, so it can take a while...

[Laney760]

Originally Posted by Laird Scooby

That's exactly what i've been saying in different words, perhaps something is getting lost in the translation?

We're not saying quite the same thing, its the actual ratio of meths:water that counts regardless of the amount of fuel in the tank so if you put the meths in when there is just a little fuel in the tank it will burn the water off quicker, if you put it in a full tank you don't need to add an extra litre of meths, you've just got to wait longer for the water to burn off

Out of interest how did you get water in your fuel? One autumn I decided to use up all the containers of fuel for the garden machinery instead of leaving it sitting over winter as usual. One had been sitting under a lean to with its pouring spout on, hadn't realised the lean to leaked! I knew immediately I next started the car I'd screwed up!

I used to run the service stations and we had to regularly check for water in the fuel tanks. If you google 'petrol stations water in fuel tanks' contamination is not unusual at all



Speedmonkey, you haven't been visiting the West coast of Norway and fuelling up there, have you?:

http://www.ybw.com/forums/archive/in.../t-161523.html

[Speedmonkey]

How did I get water in my fuel tank?

I don't know if I have water in my tank...I've got a weird misfire since I have the car. That's for 6 months now...The wise men from the web suggest adding meths to my fuel to see if things improve... That's it...

[Laney760]

Originally Posted by Speedmonkey

How did I get water in my fuel tank?

I don't know if I have water in my tank...I've got a weird misfire since I have the car. That's for 6 months now...The wise men from the web suggest adding meths to my fuel to see if things improve... That's it...

I was asking Dave how he got water in his fuel!

[Laird Scooby]

Originally Posted by Laney760

I was asking Dave how he got water in his fuel!

First car had a leaky fuel filler neck, so did the second. Third was just accumulation of condensation over 28 years.

[Dirty Rooster]

I'm subscribing to this fascinating thread.
"Spiritus" sounds so old-fashioned, I want some of that!

I would have half-removed the camshaft with the rocker cover off, leaving the front sprocket intact, just to check all the buckets move freely and the springs are good ...

[aardvarkash10]

Originally Posted by Dirty Rooster

I'm subscribing to this fascinating thread.
"Spiritus" sounds so old-fashioned, I want some of that!

I would have half-removed the camshaft with the rocker cover off, leaving the front sprocket intact, just to check all the buckets move freely and the springs are good ...

^This.

The amount of water required for a regular consistent misfire in an injected engine is pretty large. IF you suspect this is the case, wait until the tank is near empty and then remove the fuel line to the injector rail and empty the fuel into a clear container - one litre should be enough.

IF water is in the fuel it will settle and separate out - you'll be able to see it. If nothing separates out, water in the fuel is PROBABLY not your problem

[P505DEF]

Take a look at the earth strap fron engine to body.
Also swap the radio suppresion relays over
Take each injector plug off in turn to find your faulty cylinder then check the plug is connected properly, failing that check your ignition cables are the right way round, in good condition, and swap a known good cable to the defective cylinder, see if it transfers fault to another cylinder, if so the ht lead is burnt out. Also check rotor and distributor cap.