fueal additive - injector

[PNEW]

I bought a volvo 940 estate automatic recently and although my fuel economy is good for the car,
anyone else have an mpg on around town
mixed and motorway
i was thinking of adding an octane fuel additive, it says that they clean injectors and increase octane by 3 points and improve economy, has anyone tried one, are they anygood.
i worry about things that clean deposits, d they move them and bock something else. help and advice would be great

[Mr Sam]

check asda my local has the redex injector cleaner at £2 at the moment

the octane booster ones are more performance orientated, i cant say you notice the difference but on paper on the 1'4 mile they deffo work

[NewVolvo]

I've been using these cleaners for years (STP or Redex) for both petrol and diesel engines and while I can't say I have noticed any performance gains, but what I can say is that the engines always seems to get smoother and a tad quieter.

[AndyPants]

I used some redex in my 760 and it did do much better afterwards, having said this I also had a load of work done at the same time so its difficult to say whether it did actually make much of a difference. My mpg did go from 20-25mpg though in that time, and even 34 mpg on a long journey!

Going to try some again soon as the mpgs dropped a little to see if it makes much difference. Might try it in my C70 too which will be interesting since I've always run it on super unleaded (much like my 760), but thats not to say previous owners will have...

[NewVolvo]

Originally Posted by AndyPants

I used some redex in my 760 and it did do much better afterwards, having said this I also had a load of work done at the same time so its difficult to say whether it did actually make much of a difference. My mpg did go from 20-25mpg though in that time, and even 34 mpg on a long journey!

Going to try some again soon as the mpgs dropped a little to see if it makes much difference. Might try it in my C70 too which will be interesting since I've always run it on super unleaded (much like my 760), but thats not to say previous owners will have...

Interesting read.... the 760's mpg was very good. I take it it does not have a cat? My 780 (on the journey to Cologne) returned a new record of 32mpg and does not have a cat - cars with cat are supposedly taking alot more fuel (also according to a contact I have here in Germany - who also owns a 780 but only get about 25mpg!). Btw, I did not use any additives on the way down here.

[Easy Rhino]

After years of being skeptical about FI additives (cleaners), I had a couple of cars that began to run roughly that were fixed by FI cleaner additive.

I now add a bottle about once a year to each of my cars. Just the FI cleaner type.

As far as octane additives, I think that they are a waste of money, particularly for cars that do not require the high octance to prevent predetonation.

Higher octane mearely means that the gas is 'doped' to burn more slowly, which helps high compression engines prevent pinging (predetonation).

People that think that they are 'giving there cars a special treat' with the occassional high octane fill up are fooling themselves (but cannot be convinced otherwise).

[AndyPants]

Originally Posted by NewVolvo

Interesting read.... the 760's mpg was very good. I take it it does not have a cat? My 780 (on the journey to Cologne) returned a new record of 32mpg and does not have a cat - cars with cat are supposedly taking alot more fuel (also according to a contact I have here in Germany - who also owns a 780 but only get about 25mpg!). Btw, I did not use any additives on the way down here.

Yep it has no cat (B230ET so not the V6 - I imagine your figure is especially impressive for the V6!). The 34mpg was a 300 mile journey at mostly 68 indicated (63ish according to my sat nav) but the car was loaded with 3 passengers and a boot full of holiday luggage! 30mpg+ seems quite easy to achieve on longer journeys, but then I guess we know they like cruising.

Originally Posted by Easy Rhino

Higher octane mearely means that the gas is 'doped' to burn more slowly, which helps high compression engines prevent pinging (predetonation).

People that think that they are 'giving there cars a special treat' with the occassional high octane fill up are fooling themselves (but cannot be convinced otherwise).

Fair enough and octane yes, but 'premium' fuels often have more cleaners and other additives built in that can help keep things running nicely. For instance my old 850 did run better on Tesco 99 than 95 and that didn't even have a turbo. But then I believe Tesco 95 is crap, ran fine on Esso 95.

My C70 T5 gets worse mpg and performance on 95 and wouldn't try it in the 760 as in an ideal world it would enjoy 97 4-star Speaking of which I've got some lead additive I keep meaning to try in the 760 to see if it makes any difference.

[Ian21401]

I've had my 940 2.0L petrol for 6 years now. Normal domestic use to shops and work etc. The work commute is 9 miles of dual carriageway with about 1 mile of single carriageway at each end. I try to drive economicallywith no fierce acceleration and cruise at about 60 mph in 5th (2,500 rpm which I believe is at bottom end of the maximum torque revs) and I'm returning between 29 and 32 miles per gallon. About 3 years ago I read/heard about injector cleaners and have used STP since then, putting a bottle in, when the tank is half full, every 3,000 miles and it has appeared to drive more smoothly since then.

[Easy Rhino]

Originally Posted by AndyPants

Fair enough and octane yes, but 'premium' fuels often have more cleaners and other additives built in that can help keep things running nicely.

Over in the colonies the Federal Trade Comission several years ago mandated that all auto gas include the same additives whether premium, middle grade, or regular.

Suppliers had been using the "premium gas is better for your car" schtick for years, and people were sucking it up!

As long as you are using what is called a 'top tier' gas here, the higher octane is a technical waste of money unless your cars higher compression ratio requires it.

FWIW, all three of my cars (Corvette - 400HP, BMW 328i, and Volvo V90) 'require' (or at least recommend) premium fuel; however, since all have knock sensors that retard the ignition timing upon initiation of predetonation, and we rarely demand that load on them, we can run regular in them all day with no performance difference.

[AndyPants]

Originally Posted by Easy Rhino

Over in the colonies the Federal Trade Comission several years ago mandated that all auto gas include the same additives whether premium, middle grade, or regular.

Suppliers had been using the "premium gas is better for your car" schtick for years, and people were sucking it up!

As long as you are using what is called a 'top tier' gas here, the higher octane is a technical waste of money unless your cars higher compression ratio requires it.

FWIW, all three of my cars (Corvette - 400HP, BMW 328i, and Volvo V90) 'require' (or at least recommend) premium fuel; however, since all have knock sensors that retard the ignition timing upon initiation of predetonation, and we rarely demand that load on them, we can run regular in them all day with no performance difference.

Didn't notice you weren't located in the UK before But yes modern cars should cope with most sorts of fuels but personally I'd rather use whats recommended purely to have the car working at its optimum even if it will run on lower octane (pretty sure most non-turbos over here would run on 91 octane, not that I know anywhere that sells it!).

Here in the UK there are also standards for petrol so in theory it should all be pretty much the same, but in reality I don't believe that to always be the case. The difference usually boils down to more additives in the more expensive fuels. Although I will agree the differences are fairly minor in most cases. I think Turbos are the prime candidate for higher octanes which I notice none of your cars appear to be? Although I wouldn't say no to a Corvette

It would be an interesting compromise to run a car on cheap fuel but every so often to bung in some injector cleaner/additives to make up for the the 'shortfall'. But since injector cleaners cost the same as about 4 litres of fuel here themselves it probably wouldn't be worth the bother!