Mrs Pondo’s 61 plate Mitsubishi Colt has started making a noise – it sounds exactly like what in old carburettered cars you’d call pinking, or detonation, in what I remember being the same circumstances (nothing on light throttle, increases with throttle application from fairly low down). It otherwise drives fine, nothing suspicious found on yesterday’s full service. Do fuel-injected cars detonate? Is this related to that E10 thing?

The best way to stop pinking is to Adblue, then they just purple.

I’ll get my coat.

Problem with one or more spark plugs?

I’ve heard it on my seat 1.2 tsi, definitely worse on the E10 fuel. Had a couple of tanks of super and it wasn’t noticeable. Went back to E10 just recently due to the price and the pinking is back.

Pre detonation is an issue, particularly in turbocharged cars. However, most relatively modern cars will have a decent knock sensor and retard the timing if any is detected. It’s a pretty crucial safety measure.

Is it a turbo’d engine? Sure it’s not something like a heat shield slightly loose?

I don’t see why the couldn’t pink – it is simply a symptom of poor running (historically it was often due to poor fuel/air adjustment of the carb or the advance/retard of the distributor) so I would assume the new fuel might be the issue. Have you checked against the GOV.uk checker to see if that car is able to run on E10?

Yes Dacia Lodgy with Renault 1.2 TCE engine. It’s an occasional momentary thing when I increase the trottle opening up a climb. By the time I’ve realised it’s pinking it’s sorted itself out and the pinking has gone.

A lot is being made of E10 and issues on older cars. I’d look into what % of Ethanol your preferred supplier is using tbh. I work in the industry and at least one is using nowhere near 10%

Thanks folks – atmo engine, I don’t THINK it’s vibration. If we try a tankful of fancypants super rather than supeemarket regular, should that stop it, just as a diagnostic? Don’t mind if it carries on, as long as it’s not doing any harm.

Problem with one or more spark plugs?

Now that’s interesting -the nice lady said, apropos of nothing, that they looked at the spark plugs but they’re fine so didn’t change them, I don’t know if that’s on the service schedule or they spotted something previously? Might try a set of plugs – lot cheaper than a tankful of fancypants!

The best way to stop pinking is to Adblue, then they just purple.

Jesus christ.

I’d be ashamed of that one, and I have no shame.

As submarined mentioned, most modern cars have a knock sensor, so will retard the timing. Allows them to make better use of 98 RON fuel as well by advancing the timing. I’d expect a 61 plate car to be able to do that.

Assume no engine management lights or such like are on?

Might try a set of plugs – lot cheaper than a tankful of fancypants!

You’ve not bought spark plugs recently I take it? 😨

I’m not sure it would be a fault of spark plugs, unless they’re the wrong heat rating.

My understanding is that pinking/det/knock occurs when the mixture explodes too early in the stroke, before the spark plugs had actually ignited it. Usual causes in the cars I’m used to arsing about with is either too lean a mixture (so it gets too hot and explodes too early) or timing too far advanced. (Or too much boost, but that’s not the issue here if it’s an NA engine!)

I’d start by getting it plugged in to see what any stored codes are. I’d be surprised if any reasonably modern ECU didn’t act off a decent knock sensor of any det was detected. My early 90s washing machine engine picks up on it! (But the ECU doesn’t do anything about it…)

Dodgy knock sensor? Even cars from the 80’s had knock sensors. It should pull timing a certain amount until knock/load changes.
They literally just bolt to the block on older cars. No idea about modern stuff.

A few months ago I had one wired directly to the stereo line in to see what I could hear. Was mostly just the sound of the valve train and injectors.

Dodgy knock sensor?

Obvious thing to check.

Allows them to make better use of 98 RON fuel as well by advancing the timing

don’t know about really modern stuff but that didn’t used to be the case, a knock sensor could retard the timing but not advance it past what it was originally mapped at by the manufacture so it was only certain performance cars mapped for 98 fuel that got that benefit.
the integra i had used 98 but the knock sensor allowed 95 in an emergancy, only did it once and the differance was very noticable.

My dad used to mention ‘pinking’ on my bros old 86 mini. I never had a **** clue to be honest but used to throw in ‘ Sounds like it’s pinking a wee bit ‘ randomly to my pals pride and joys.
Still dont know what It means.

used to throw in ‘ Sounds like it’s pinking a wee bit ‘ randomly to my pals pride and joys.

interesting. my friends used to say this about their own cars. i never had a clue. i just agreed

Still dont know what It means.

The spark plugs are always fired before the piston reaches top dead center so that the fuel/air charge is burning properly for the power stroke. This is called the ignition advance. At low revs and/or high throttle openings, you need less ignition advance than at high revs or low throttle opening. If you don’t have enough ignition advance, you sacrifice power. If you have too much, the pressure inside the combustion chamber becomes too high and the fuel/air charge detonates instead of burning in a controlled manner. This creates a shock wave that can damage pistons. You can also hear it audibly as a “pink” noise, vaguely like bottles being clinked together.

Modern cars, especially turbos, have knock sensors and retard the ignition to control pinking. Before electronic ignition and electronic fuel injection, cars had mechanical distributors and carburetors. The fuel/air mixture was not controlled as precisely and the carburetors used spring loaded weights to retard the ignition timing as engine speed increased, plus a vacuum advance to increase it for low throttle cruising (when there is high vacuum in the inlet manifold). These were pretty crude so it was fairly normal to set the timing by ear. You would keep advancing it (by loosening a clamp and physically rotating the distributor) until you got pinking under heavy load, then you would back it off just enough to stop the pinking. Thing is, having the ignition set to the optimum static advance would probably still induce pinking in extreme situations. For example, my dad’s car always used to pink towing a caravan up a specific hill. That would have been full throttle at a specific engine speed. Also, in cold weather, air is denser and that might be enough to induce pinking, or different fuel blends might be enough to do it. It’s something that anyone who’s driven a pre-electronic ignition car is used to, but pretty much just disappeared after 1990 or so.

I recently pinked a brand new prototype engine to death.

Bad calibration kills engines.

Opening up the hood to see what had happened was interesting!

I had understood that Ethanol increases octane rating, so I am not sure why E10 would make pinking worse?

I had horrendous pinking with my wifes golf. 1.4 tsi on supermarket petrol. Took it to VW who stated that its something they often see with poorer quality fuel.

had understood that Ethanol increases octane rating, so I am not sure why E10 would make pinking worse?

Something something calorific value something. Over my head.
My very fragile engine was mapped for V Power, strong warnings about not using Tesco 99, as it has a much higher ethanol content, which can be enough to cause bits of it to try and fall out of the exhaust.

what engine is that?

https://www.rac.co.uk/drive/advice/emissions/what-is-e10-fuel-and-how-could-it-affect-you/

there you go. they say it can pink as well

I had horrendous pinking with my wifes golf. 1.4 tsi on supermarket petrol.

Interesting, I would not have expected that on a TSI engine.

FWIW our Zafira (1.4t) struggles on E10 petrol. After a tank or two it chucks out an engine warning light and SWMBO said it didn’t “run well”. Took it to local garage who said Vauxhalls tend to run lean so they recommend going to E5.

Funnily enough I routinely fill it with super anyway, but wifey sticks any old shite in it. And the problem always used to come up when she’d filled it.

Since we changed to only super (or a branded petrol if we can’t get E5) we’ve had zero issues.