Variable and lumpy idling.

[Laird Scooby]

Thanks for the Toolstation tip! Getting 2L there in one bottle is a big saving!

The Wynns stuff is only 325ml so pence per ml is considerably higher, something like 3p/ml whereas the meths is £6.61 for 2000ml which works out as 0.331p/L - quite a saving!

Also the big thing is the concentration, the amount of water in the tank won't change, adding something like meths or Wynns to a full tank dilutes it as it needs to work on the water which will sink to the bottom of the tank when stationary. With a full tank the meths/Wynns is held in suspension in the petrol so has less of a chance of mixing with the water before being burned.

[tedbriggs]

Had same problem on mine it was water in the carb the engineer said

[Delta66]

The Wynns stuff does claim it is formulated for one tank of petrol, but it did not say it was best used when full or empty. I had a full tank, so in it went.

It is clearly making a difference, so I think a long drive is in order as I want to stop the power loss asap. At least when it does happen, people see an old car and hopefully realise it is the car not the driver causing the problem!

[Laird Scooby]

I've never quite got how they can say it treats "one tank of fuel". Is that a Mini tank at 8 gallons ish or a Jag XJ40 tank at 21 gallons?
Or do they mean the majority of tanks that fall into the 12-15 gallon size?

That's why i prefer to drive until the "feed me" light comes on or the needle touches the red, both indicate about 2 gallons left in most cars, add 2L of meths and 2 gallons of fuel (total fuel now about 4 gallons/18L and meths 2L so 10% concentration) as this has been tried and tested by several people i know of and know it works.

It also gives almost instant results because firstly you're dealing with a much smaller quantity of fuel and secondly, the concentration is that much higher.

What does bother me in a related way is that apparently fuel containing ethanol is going to be sold in this country. The problem with that is it contains a higher water content than normal fuel so this could become much more of a problem for us all.

[Delta66]

Maybe it is how much water they think is likely in a tank, no matter the size of the tank.

[Laird Scooby]

That's a very viable theory and goes with their recommendation to use every 6 months.

Got to be based on an average taken almost at random though.

[Delta66]

I am just happy the addative is working and it is not another fault. They should warn ther can be a possible loss of power for a second or two. It is scary when doing 60 in traffic on a busy country road and the car starts to slow for no apparent reason.

[Laird Scooby]

I'm beginning to get the impression the additive is meant as a prevention rather than a cure, especially as they recommend using it every 6 months. It's probably only designed to cope with a small amount of water that would build up in this time.

If you find it's still doing it after you've used the additive, i think a trip to Toolstation would be in order, use a funnel at the filling station to pour the meths in first then add a couple of gallons to a near-empty tank.

That should give you a "yay or nay" much quicker!

[Laird Scooby]

I've just looked up the MSDS sheets on both Wynns Dry Fuel and Toolstations Meths :

https://cdn.aws.toolstation.com/items/coshh/99550.pdf

https://www.wynns.uk.com/wp-content/...03.00-en-1.pdf

Spot the difference in composition! There's a couple of small differences but largely the Wynns product is...........................

drum roll please......................

Methylated Spirits!

That really reinforces my theory it's meant as a prevention rather than a cure, simply on quantity used and the resultant concentration.

[Delta66]

I removed the idle control valve, cleaned it with carb cleaner, replaced and the the running is less lumpy and the idle revs now sit about 900 rpm. The valve looked clean, but quite a lot of crud came out.

I cannot find what is the correct idle revs for the 2.3 lpt. Anyone know?