Pinging at 100kph+

[Lil'Loki]

Hey everyone,

I have what I think may be 'light pinging' at 100kph+.
There is no pinging with heavy acceleration, only when at the top end between 100 - 120kph. With the softtop (wind and flapping noise at high speed) it is very hard to hear and if it is, it is very light pinging.

As there is no pinging during acceleration, I believe timing is not the issue.
I feel that the fuel may be the cause. Normally I run 95 octane as this gives me better fuel economy, the last two or three times I've used the regular 91 octane unleaded.

The car is due for its service this week, so I can check the timing, but I really believe fuel octane level is the issue.

Any suggestions or anyone agree that I'm on the right track?

Thanks Darren

[GRPABT1]

If you care about your car you'd use BP ultimate. Not only for the octane rating but for the fact it is alot cleaner. I've always stuck by this stuff.

[zook4fun]

could be your vac advance on the dizzy is stuffed and not coming back down when you lift your foot off the gas. check it moves pretty easy and springs back.

thats what i would check 1st

[NIK]

Are you running the stock carb, it may be leaning out to much at higher rpm?
Nik

[Squik]

If you care about your car you'd use BP ultimate. Not only for the octane rating but for the fact it is alot cleaner. I've always stuck by this stuff.

What he said and Caltex Optimax is good too. Stay clear of the ethanol mixes... or the pinging will drown out your iPod!

[GRPABT1]

Isn't optimax shell?

[MUD-PIGSIERRA]

Unless your running a high compression ratio engine or turbo or supercharger you have no need to run a high octane rated fuel. I don't know anything about your 4by here so in the case it was one of the above running a lower rated unleaded fuel would be a problem. Or running advanced timing could also possibly cause this...? Other things that can cause this is modifications on air ducting through your carby change or excessive engine revs (Bigger tires) being stuck in 4th gear cos you cant use 5th. Excessive or above normal head temperatures also can contribute to this. Another thing others get confuse this with is pre-ignition which can be caused from hot spots or spark plugs in bad condition. You might also be able to see this when shutting your engine of when it sort off half dies of and splutters to a stop.

The higher rated fuel is for resisting detonation on compression before your spark comes on not about giving you more power. If its going 100km maybe the switch from gearbox is not working for 5th gear....?

Stay clear of the ethanol mixes... or the pinging will drown out your iPod!

Ethanol petrols actually have a higher detonation point than normal Unleaded so this would be highly unlikely as well. I also have been running it since it came out as its cheaper and have not noticed any difference with my engine or had any problems.

[Squik]

When I picked up the Jimny, it had a gut-full of E-Petrol and was pinging it's ring off.
I gave it a load of 98O once that tank was done, and it hasn't done it since... enough to convince me...

[rustyzook]

you lot have no sence of adventure, its not pining, its sining along with you, its beat. lol.

[Santos]

When I picked up the Jimny, it had a gut-full of E-Petrol and was pinging it's ring off.
I gave it a load of 98O once that tank was done, and it hasn't done it since... enough to convince me...

i'm tired of defending ethanol fuels, i had a friend tell me that ethanol LOWERS the octane rating of fuel and thats why it was sold cheaper.

I tried to explain that Ethanol increases octane rating, so by mixing ethanol with petrol, petrol companies can resell sub-standard petrol by bringing it back above 91 RON with ethanol.

Caltex, shell and BP all sell 92 RON E10, i have put it in my tank a few times when i am half empty but i regularly fill up with 95-98 RON so the odd occasion is ok. What i tend to have is 98 Vortex then 2-3 tank fulls of 95-98 RON e10 that i get at two separate servos. I have been doing this for almost 4 years and clocked up over 40000k's.

The reason why i go vortex is purely is i have noticed that if i stick to one fuel my economy slowly drops off if i use only one fuel (this includes only using vortex!) and i work for Woolworths so i do get 4c off a litre without a docket. Also i tend to fill up when i am 1/3- 1/2 full.

Engines can ping on any fuel if its off, the thing i notice is people will not think twice if they had a bad batch of regular and fixed it with 98 ron but the same thing happens on E10 and they will not use it again

I also have reved my engine out to redline several times, i prettry sure there was no pinging (i often here it from commodores magnas and falcons when walking down the street) If everything stock then i don't think the carb is leaning out without something else being the culprit (timing, advance, blocked jets blah blah)

[Lil'Loki]

Unless your running a high compression ratio engine or turbo or supercharger you have no need to run a high octane rated fuel. I don't know anything about your 4by here so in the case it was one of the above running a lower rated unleaded fuel would be a problem. Or running advanced timing could also possibly cause this...? Other things that can cause this is modifications on air ducting through your carby change or excessive engine revs (Bigger tires) being stuck in 4th gear cos you cant use 5th. Excessive or above normal head temperatures also can contribute to this. Another thing others get confuse this with is pre-ignition which can be caused from hot spots or spark plugs in bad condition. You might also be able to see this when shutting your engine of when it sort off half dies of and splutters to a stop.

The higher rated fuel is for resisting detonation on compression before your spark comes on not about giving you more power. If its going 100km maybe the switch from gearbox is not working for 5th gear....?

Stay clear of the ethanol mixes... or the pinging will drown out your iPod!

Ethanol petrols actually have a higher detonation point than normal Unleaded so this would be highly unlikely as well. I also have been running it since it came out as its cheaper and have not noticed any difference with my engine or had any problems.

95 Sierra - Engine and Head recently rebuilt (only about 8000km's on it)
Lukey Extractors throught 2" exhaust with sports muffler.
235x75x15's (No Gearing) 100kph on Speedo = (110kph actual speed)
Can cruise in 5th at 100kph (110kph) no problems
Current Carby is stock from an earlier model zook circa 91. (Mine is 95)
Original 95 Carby (now spare) needs kitting - current 91 carby is only 21mths since it was kitted/rebuilt.

Tried GRPABT1's advice and filled the 3/4 tank of 91 octane with BP 98 octane (managed to squeeze 10L of 98 in to the tank). Took the Zook for a run on the freeway 120kph (132kph actual) southbound with slight breeze from behind.
Could have probably got her up to 125-130kph (143kph) but didn't want to push my luck with the 'Sunday Driver' traffic and Road Nazi's cousins in the West. No Pinging at All

Exited the off ramp crossed the freeway and headed northbound. Slight head wind 95kph (104.5kph) No Pinging again.

Now with regular driving (non freeway or speeds over 80kph) the Zook idles at 800rpm… BUT, after opening her right up (100kph+) and exiting the freeway the Zook idles at 1200rpm which is starting to make me think that Zook4Fun has a possible point about the vacuum advance having issues.

I paid a fair bit for my mechanic to rebuild the engine (some guy's on outers have given me a bit of a ribbing about what I paid…:finger: ) but I'm pretty happy with the performance I get from the little 1.3 motor.
I don't abuse the motor but I also don't baby it. So the 'light pinging' (now gone) and higher idle speed after giving it sh1t aren't a big problem, but I'm just a fussy ba5tard

My mechanic is going to check the timing and vacuum advance for me this week. I'd do it myself but my timing light is 40yr's old (from Dad) and throws a pi55 weak light which makes it hard to see the timing mark.

Thank again guys.

[MUD-PIGSIERRA]

So its quite possible with your engine rebuild and head rebuild the head could have been shaved giving you a higher comp. ratio....?

What ever anyone says I think the whole Ethanol mixed fuel is sorta like when the lead replacement fuel came out obviously some cars really cant run this fuel but, people blamed the fuel for other existing mechanical issues or bad performance from the engine....?

I noticed a lot of the new cars coming out also carry stickers near the fuel filler or in side the door saying its safe to run Ethanol type fuels so it cant all be that bad, plus people that buy "Octane Booster" from servos or car parts stores what do you think is in your Octane booster....

[Lil'Loki]

So its quite possible with your engine rebuild and head rebuild the head could have been shaved giving you a higher comp. ratio....?

What ever anyone says I think the whole Ethanol mixed fuel is sorta like when the lead replacement fuel came out obviously some cars really cant run this fuel but, people blamed the fuel for other existing mechanical issues or bad performance from the engine....?

I noticed a lot of the new cars coming out also carry stickers near the fuel filler or in side the door saying its safe to run Ethanol type fuels so it cant all be that bad, plus people that buy "Octane Booster" from servos or car parts stores what do you think is in your Octane booster....

There may have been some shaving/decking of the head, don't think it would have been much though.

[alien]

most octane boosters ingredients list reports "100% hydrocarbons" - i thought hydrocarbons was basically hydrogen and carbon, and not ethanol?

Here in WA theres not many servo's selling E10 or even E5... im sure if they did people would buy it - i'd even give it a shot to see how it went... if it saves 10c per litre over 3 tanks then you pay +20c for 98 ron, you're still 10c a litre ahead at the end of the month... petty, but better in my pocket than someone elses =P

[Gwagensteve]

Despite ethanol having a higher effective octane, it's less thermally efficient than petrol so the air/fuel is richer to achieve stiochiometric. As a result, for the same amount of power you'll use more ethanol than petrol.

I ran some Shell Vpower Racing (100 octane, 10% Ethanol) in my Mini and lost fuel economy.

My guess is you won't save money running E10.

Steve.

[zook4fun]

ethanol only causes problem when is a high mix sat 30% and up, all the stuff few years ago was becaused servos were running up to 60% ethanol (cheaper for them to buy) and selling it as petrol. thats when it will kill your lines and seals. now its limited buy law to how much they can put in.

[Santos]

Despite ethanol having a higher effective octane, it's less thermally efficient than petrol so the air/fuel is richer to achieve stiochiometric. As a result, for the same amount of power you'll use more ethanol than petrol.

I ran some Shell Vpower Racing (100 octane, 10% Ethanol) in my Mini and lost fuel economy.

My guess is you won't save money running E10.

Steve.

Vpower racing is E5 (5%)

is the mini running the stock ignition and compression?

100 octane might be a little high for such an engine, the fuel might not be burning completely dropping the fuel economy.

The hardest thing for ethanol, lpg and other fuels is people often compare it on engine that designed to run regular. Who pays out a rugby team out for failing to beat soccer team playing soccer?

Build an engine to perform on lpg or on ethanol or whatever and it will flog the result with thesame engine on petrol. Diesel have had the same issue for years and now they are all the rage

[Gwagensteve]

"While the stoichiometric (chemically ideal) air/fuel mixture ratio for gasoline is approximately 14.7:1, with ethanol it is around 9.79:1. ..."

The hardest thing for ethanol cars isn't that the engines aren't made for it, it's more that you just need more of it to make the same power.

Modern EFI engines will achieve Stoichiometry lambda=1 regardless of how much ethanol is in the fuel (within reason) but the more ethanol in the blend, the worse economy will be. If the fuel wasn't burning fully, the O2 sensor(s) would read rich, and the ECU will pull fuel out That's not happening though.

Yes, an ethanol motor will allow more timing and more compression than a petrol motor, but it will still take more ethanol to make 1kw than to make 1kw with petrol, so yes, peak power can be higher with ethanol (as in the biofuel Koenigsegg, where it picks up about 20% power on E85, but I haven't seen any fuel economy figures for it

Lambda 1 for diesel is very, very close to petrol - 14.9:1 from memory.

Steve.

[Santos]

Chevrolet Omega, produces same economy and more power on ethanol than petrol

We call this car a Holden commodore

[Santos]

i just typed a really long argument drawing parrallels to lpg -and lost it when i hit submit.

Anyway i will add the last bit which was bringing it back to topic.

I don't think E10 or E5 will reduce fuel economy on their own, the quantity is so small that any ' leaning out' wouldn't be that great. Also the fact that ethanol can absorb a lot more heat during vaporisation means that cylinder temparuters can be lower.

Running e10 95 Ron regularly is what i recomend for a stock suzuki 1.3l, 92 base stock can't of been in good condition to begin with and 100ron makes it way to hard to ignite.

[Gwagensteve]

Well E5 did measureably reduce my economy, in a new engine with knock sensing, 2 oxygen sensors, boost and very modern ECU technology, with an engine, intended to run ethanol across the world market.

This parallels the science of the performance of this fuel.

No, in a carby sierra, the ethanol probably won't make much difference to anything in particular in relation to the performance of the motor, but why would you recommend it? Ethanol is hell on fuel system parts not intended for it.

Steve.

[ScrawnC]

Ethanol is hell on fuel system parts not intended for it.

This is my number reason for staying away from it, I don't care too much for fuel economy. This stuff will rot the fuel system out. (Granted in very small doses it won't have the same effect)

[Lil'Loki]

You lot are a bunch of thread hijackers

How about I change the topic line from Pinging at 100k's+ to the Pro's and Con's of Ethanol!

You all could then debate this about becoming a topic for the Bible's!

[Santos]

Thread terrorism is something i am guilty of, but still i thought when you put 98ron fixed it (or did it only temporaly go and then come back)

[zook4fun]

is got to be your vac advance then its getting stuck and putting to much timing in the engine. i'd go spray some wd 40 in the dizzy and move it round a bit clean it back up and see how it goes.

[Lil'Loki]

Thread terrorism is something i am guilty of, but still i thought when you put 98ron fixed it (or did it only temporaly go and then come back)

I'm sure this has corrected the problem.

I was only taking the p!55, thought about changing the topic title so other members could find it easier. Especially as fuel and its alternatives are a big topic of discussion these days.

Thanks again guys, and I'll be sure to try Zook4Fun's suggestion in regards to the vacuum advance.

[Lil'Loki]

Thread terrorism is something i am guilty of, but still i thought when you put 98ron fixed it (or did it only temporaly go and then come back)

I'm sure this has corrected the problem.

I was only taking the p!55, thought about changing the topic title so other members could find it easier. Especially as fuel and its alternatives are a big topic of discussion these days.

Thanks again guys, and I'll be sure to try Zook4Fun's suggestion in regards to the vacuum advance.

My mechanic mate adjusted the vacuum advance checked the timing and gave it a bit of a tune up. He reckons it may have a little more power now . The power wasn't really the issue, just the erratic idle speeds after a good run on the freeway and the slight pinging (now fixed). Will be going for a surf tomorrow (hopefully if there's some swell), will see how it goes .

[brendan_h]

what does a ping sound like? this is a serious question

[Lil'Loki]

It's hard to describe… closest description I can think is it's like 'Marbles bouncing around in a big jar being rolled down an incline'

[Gwagensteve]

Not a bad description Lil' loki.

It can be quite hard to hear when it's mild. Imagine a kind of random "pitter patter"of "tink" noises - that's how I'd describe it.

Steve.