Ive been advised to run 95 in my old '84 Sunny.. but its really scarce...

Does anyone know of an additive available to add to 91 so i can use that..?

Does the engine pink (ping) under load, or knock ? If not l wouldn't worry. If it does with 91 and not with 95 then perhaps an additive.

It's an old engine and compression will not be what it was for the need of higher octane.

Does the engine pink (ping) under load, or knock ? If not l wouldn't worry. If it does with 91 and not with 95 then perhaps an additive.

It's an old engine and compression will not be what it was for the need of higher octane.

Many people talk of 'pinging'.. what exactly am i listening out for..? if ive just filled up with 91 and it 'pings' what should i do..? Empty the tank..?

Is this pinging easy to recognize?

Does the engine pink (ping) under load, or knock ? If not l wouldn't worry. If it does with 91 and not with 95 then perhaps an additive.

It's an old engine and compression will not be what it was for the need of higher octane.

Many people talk of 'pinging'.. what exactly am i listening out for..? if ive just filled up with 91 and it 'pings' what should i do..? Empty the tank..?

Is this pinging easy to recognize?

Pinking (pinging) is easy to hear - it sounds there's marbles in the engine when accelerating (especially under heavy accelaration).

Does the engine pink (ping) under load, or knock ? If not l wouldn't worry. If it does with 91 and not with 95 then perhaps an additive.

It's an old engine and compression will not be what it was for the need of higher octane.

Many people talk of 'pinging'.. what exactly am i listening out for..? if ive just filled up with 91 and it 'pings' what should i do..? Empty the tank..?

Is this pinging easy to recognize?

If you load your car by starting off at low speed and accelerating hard or stopped with the brake on and give it some throttle and if it sounds like a diesel instead of a petrol car it's pinging or dieseling as it's termed. By the way turn off the air and open a window to listen better best next a wall down a quiet street to here the echo back to you as it may be faint.. If it's manual you can do this by just putting it in second or third gear and trying to start from a standing stop and it will ping if the octane is too low, but also a timing tune up may be advised as much of the pinging can be tuned out with a timing adjust though it may not be quite as sprightly in performance it will be much better then pinging for the engine..

As the guys say, put your foot down and the engine rattles, especially if your in too high a gear. Really bad fuel will pink every time you accelerate until your at your cruise speed.

If there is no difference in the sounds coming from under the hood then don't worry about the lower octane.

As the guys say, put your foot down and the engine rattles, especially if your in too high a gear. Really bad fuel will pink every time you accelerate until your at your cruise speed.

If there is no difference in the sounds coming from under the hood then don't worry about the lower octane.

a US spec, as sold in LOS, 84 Nissan runs fine on 91, usually down to 89, so its going to be hard to spot any ping at all, unless the pistons are very sooted, thus increased compression

Top gear 1200rpm and full thottle, if it sounds like a diesel, have ignition timing adjusted. If it still sounds like a diesel, you need an octane booster additive.

Don't know what the hell US spec means?? We're talking about Thailand here and last I knew we don't even have Nissan NV's in the states.

The diagnostic procedure is universal, applicable and works just as well on any engine no matter where, it's certain I could diagnose it with the simple procedure mentioned regardless of how minimal the sound, however there is obviously no way to prove that to you so you'll just have to take my word for it..

As the guys say, put your foot down and the engine rattles, especially if your in too high a gear. Really bad fuel will pink every time you accelerate until your at your cruise speed.

If there is no difference in the sounds coming from under the hood then don't worry about the lower octane.

a US spec, as sold in LOS, 84 Nissan runs fine on 91, usually down to 89, so its going to be hard to spot any ping at all, unless the pistons are very sooted, thus increased compression

Top gear 1200rpm and full thottle, if it sounds like a diesel, have ignition timing adjusted. If it still sounds like a diesel, you need an octane booster additive.

Dont know what you mean by that the pistons are carboned up, that the compression will be higher? if the piston is carboned [or sooted] it usually means the valve guides and seats are worn and the piston rings are worn as well, thus lowering compression, even a worn turbo charger thrusting oil mist into the engine will not cause cokeing,carboning,sooting, the only time ive seen this was with BMC cars when old people forgot to push the choke in,

As for the OP, a weak fuel mixture could be the problem, the petrol fuel here does have a low life before it clogs your carb jets, getting the carb/s cleaned out would be a good start..

Don't know what the hell US spec means?? We're talking about Thailand here and last I knew we don't even have Nissan NV's in the states.

The diagnostic procedure is universal, applicable and works just as well on any engine no matter where, it's certain I could diagnose it with the simple procedure mentioned regardless of how minimal the sound, however there is obviously no way to prove that to you so you'll just have to take my word for it..

most engines come in at least 2 specs, US and Euro. US usually less on power and fuel demand. Most Thai sold/made cars are US spec engines (and suspension for that matter).

Take a modern engine like 2008 Honda 2,4. US (and Thai) is 180hp and needs 91, Euro is 200hp and needs 95 fuel.

Don't know what the hell US spec means?? We're talking about Thailand here and last I knew we don't even have Nissan NV's in the states.

The diagnostic procedure is universal, applicable and works just as well on any engine no matter where, it's certain I could diagnose it with the simple procedure mentioned regardless of how minimal the sound, however there is obviously no way to prove that to you so you'll just have to take my word for it..

most engines come in at least 2 specs, US and Euro. US usually less on power and fuel demand. Most Thai sold/made cars are US spec engines (and suspension for that matter).

Take a modern engine like 2008 Honda 2,4. US (and Thai) is 180hp and needs 91, Euro is 200hp and needs 95 fuel.

Ok now I understand you're reference...I didn't know you were comparing US spec to Euro I understood you were comparing US to Thailand which you've rightly pointed out is the same..

Don't know what the hell US spec means?? We're talking about Thailand here and last I knew we don't even have Nissan NV's in the states.

The diagnostic procedure is universal, applicable and works just as well on any engine no matter where, it's certain I could diagnose it with the simple procedure mentioned regardless of how minimal the sound, however there is obviously no way to prove that to you so you'll just have to take my word for it..

most engines come in at least 2 specs, US and Euro. US usually less on power and fuel demand. Most Thai sold/made cars are US spec engines (and suspension for that matter).

Take a modern engine like 2008 Honda 2,4. US (and Thai) is 180hp and needs 91, Euro is 200hp and needs 95 fuel.

Ok now I understand you're reference... I didn't know you were comparing US spec to Euro I understood you were comparing US to Thailand which you've rightly pointed out is the same..

As the guys say, put your foot down and the engine rattles, especially if your in too high a gear. Really bad fuel will pink every time you accelerate until your at your cruise speed.

If there is no difference in the sounds coming from under the hood then don't worry about the lower octane.

a US spec, as sold in LOS, 84 Nissan runs fine on 91, usually down to 89, so its going to be hard to spot any ping at all, unless the pistons are very sooted, thus increased compression

Top gear 1200rpm and full thottle, if it sounds like a diesel, have ignition timing adjusted. If it still sounds like a diesel, you need an octane booster additive.

Dont know what you mean by that the pistons are carboned up, that the compression will be higher? if the piston is carboned [or sooted] it usually means the valve guides and seats are worn and the piston rings are worn as well, thus lowering compression, even a worn turbo charger thrusting oil mist into the engine will not cause cokeing,carboning,sooting, the only time ive seen this was with BMC cars when old people forgot to push the choke in,

As for the OP, a weak fuel mixture could be the problem, the petrol fuel here does have a low life before it clogs your carb jets, getting the carb/s cleaned out would be a good start..

No answer was the stern reply..

As the guys say, put your foot down and the engine rattles, especially if your in too high a gear. Really bad fuel will pink every time you accelerate until your at your cruise speed.

If there is no difference in the sounds coming from under the hood then don't worry about the lower octane.

a US spec, as sold in LOS, 84 Nissan runs fine on 91, usually down to 89, so its going to be hard to spot any ping at all, unless the pistons are very sooted, thus increased compression

Top gear 1200rpm and full thottle, if it sounds like a diesel, have ignition timing adjusted. If it still sounds like a diesel, you need an octane booster additive.

Dont know what you mean by that the pistons are carboned up, that the compression will be higher? if the piston is carboned [or sooted] it usually means the valve guides and seats are worn and the piston rings are worn as well, thus lowering compression, even a worn turbo charger thrusting oil mist into the engine will not cause cokeing,carboning,sooting, the only time ive seen this was with BMC cars when old people forgot to push the choke in,

As for the OP, a weak fuel mixture could be the problem, the petrol fuel here does have a low life before it clogs your carb jets, getting the carb/s cleaned out would be a good start..

No answer was the stern reply..

Well Lickey, the beauty of internet forum discussions, is that we all choose when and what to write or reply to

Pistons and valves can be sooted even on fairly new vehicles (20k km) due to much idling or low revs or clogged airfilter, and the valves and seats can still remain in good condition. This increases compression slightly and can demand higher octane to avoid pinging.

Solution, blow soot out by keeping the revs up for a couple of hours. Speedlimits may restrict this to be done in 2nd gear at 90kmh. Check oil when done as it can be very black and low.

Typical for a Scandinavian car with speed limits 110kmh, go to German Autobahn at +200kmh, initially exhaust is dark but within couple of hours exhaust is clean and often oil dark. Oil makers call it black slurge.

With my Vigo 2009 petrol automatic 2.8 litre I find that there is no difference in the apparent running, power on hills etc seem about the same, no pinging, however there is a difference in fuel consumption and that is more or about the same as the difference in price. I use gasohol exclusively now.

With my Vigo 2009 petrol automatic 2.8 litre I find that there is no difference in the apparent running, power on hills etc seem about the same, no pinging, however there is a difference in fuel consumption and that is more or about the same as the difference in price. I use gasohol exclusively now.

your inline 4 is 2,7 litre

With my Vigo 2009 petrol automatic 2.8 litre I find that there is no difference in the apparent running, power on hills etc seem about the same, no pinging, however there is a difference in fuel consumption and that is more or about the same as the difference in price. I use gasohol exclusively now.

your inline 4 is 2,7 litre

ok a typo....still a reasonably good allrouder.

With my Vigo 2009 petrol automatic 2.8 litre I find that there is no difference in the apparent running, power on hills etc seem about the same, no pinging, however there is a difference in fuel consumption and that is more or about the same as the difference in price. I use gasohol exclusively now.

your inline 4 is 2,7 litre

ok a typo....still a reasonably good allrouder.

But under powered for a big ride, quiet but...........

^Face it, everything below a 454 V8 crate engine is underpowered to you ..

Dont know what you mean by that the pistons are carboned up, that the compression will be higher? if the piston is carboned [or sooted] it usually means the valve guides and seats are worn and the piston rings are worn as well, thus lowering compression, even a worn turbo charger thrusting oil mist into the engine will not cause cokeing,carboning,sooting, the only time ive seen this was with BMC cars when old people forgot to push the choke in,

As for the OP, a weak fuel mixture could be the problem, the petrol fuel here does have a low life before it clogs your carb jets, getting the carb/s cleaned out would be a good start..

No answer was the stern reply..

Well Lickey, the beauty of internet forum discussions, is that we all choose when and what to write or reply to

Pistons and valves can be sooted even on fairly new vehicles (20k km) due to much idling or low revs or clogged airfilter, and the valves and seats can still remain in good condition. This increases compression slightly and can demand higher octane to avoid pinging.

Solution, blow soot out by keeping the revs up for a couple of hours. Speedlimits may restrict this to be done in 2nd gear at 90kmh. Check oil when done as it can be very black and low.

Typical for a Scandinavian car with speed limits 110kmh, go to German Autobahn at +200kmh, initially exhaust is dark but within couple of hours exhaust is clean and often oil dark. Oil makers call it black slurge.

I will agree to disagree on this one, i would say that modern fuel injection systems petrol or diesel give a monitored amout of fuel according to engine speed, whether its working or ticking over, as an eg, in 2004 i was called out to a pumping station on the Fens in the UK, the engigine was makiking chuffing noises in the air filter, i found a tight inlet tappet, adjusted it and it sounded ok, boss said take the head off to be sure the valve is ok, so odered the gaskets ect and took the head off, no problems with the valves, now this engine is a Crossley flat 4, from 1933, it is left ticking over for 4 months of the year, about 90rpm, because they are such a bugger to start,, Max HP 380 at 620rpm, the piston was clean, ok, a little damp with unburnt fuel, but no soot or cokeing, not bad for 70+ years service, so if you have some pics of a 20.000k pick-up engine, coked up, will be glad to see them,

Thankyou, Lickey,,

^Yes, but he isn't talking about a modern fuel injection system, the OP is in regards to an older model carburated Sunny so many other factors have to be taken into account...

Which i have already mentioned about low fuel life and clogged jets,

For instance, if im not going to use my XJR 1200 Yamaha for 2 weeks, i drain the carbs, otherwise [even though i use 95] the fuel coagulates and the engine runs weak and backfires a lot, The extra heat ruins the spark plugs, so spending 10 mins draining the carbs saves me 260bht and an hours work for 4 new plugs,