Octane Booster to Avoid Burnt Valves

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Yellow_Polo
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Drives: 9N3, 2005, 1.2, 3 Pot
Location: Gloucestershire

Octane Booster to Avoid Burnt Valves

Post by Yellow_Polo »

Hi everyone and thanks for reading.

In a sentence, I'm looking to avoid Burnt Valves....

I've read that premium Unleaded Fuel (I'm in the UK) in my recently purchased 1198cc Polo can avoid issues with burnt valves.

Its a 3 pot, on a 55 plate; I'm pretty sure from the rear clusters its the Facelift 9N3

Its fine, but it does pink a bit below 2000revs especially from a stand-still.

Does anyone have any thoughts about Premium Unleaded or an Octane Boosting Additive: is one preferable over another, or are they just a waste of money? Is my information about Burnt Valves true?

Its a family car and we're aged in our 40's, so its not thrashed, I never rev it beyond 4000rpm. Only 74k on the clock and runs nicely

and... is an average fuel consumption of about 38mpg about right. Its mostly used on rural roads at about 50mph and motorways at 70-75mph....so a figure that's only in the 30's seems frankly rubbish! (but I'm more used to a Diesel)
RUM4MO
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Re: Octane Booster to Avoid Burnt Valves

Post by RUM4MO »

I can't comment from experience about using higher octane fuel helping with avoiding burnt valves, but from reading these forums, I'd think that valves end up getting damaged due to the holes in the head wearing out so the valves can wobble and that can cause damage as they will now not be sealing up on their seats.

Pinking, I've had that on a 2002 Polo 9N 1.4 16V 75PS petrol engines car, and it was due to the oil separator stopping being effective, so more than acceptable volumes of engine oil was being allowed to get into the inlet side with the incoming air, and being burned by the engine, this oil fooled the Lambda probes into backing off the basic fuelling and so ending up with pinking even at low revs and average to high engine load even in cold weather - the resulting "fuel mixture" had a lower octane rating than the engine desires due to the petrol dilution by the engine oil so certainly not a 95 octane effective fuel.

I just replaced the oil separator with a new genuine after suffering this going on for a few years and keeping the pinking away by using 97 or 98 octane petrol, which made the "low end" drivability almost acceptable - while not improving but maybe even dropping the MPG slightly, that car used in rural running could return roughly 40MPG in winter, so your 38MPG does not sound too good!

Does that car use much oil to back my theory that you have an oil separator problem?
Yellow_Polo
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Joined: Thu Jan 02, 2020 8:33 pm
Drives: 9N3, 2005, 1.2, 3 Pot
Location: Gloucestershire

Re: Octane Booster to Avoid Burnt Valves

Post by Yellow_Polo »

Thanks for taking the time & trouble Rum :D . This one isn't using any oil, so no issue with the oil separator
RUM4MO
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Drives: B8 S4 & 6R/6C1 1.2TSI 110
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Re: Octane Booster to Avoid Burnt Valves

Post by RUM4MO »

Bummer - maybe, as that would be an easy fix!
littlepolo
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Re: Octane Booster to Avoid Burnt Valves

Post by littlepolo »

Under what conditions does it pink (engine temp, season, ambient temps, etc.)?
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