SMOKE billowed across the A27 near Holmbush on Monday morning as a van engine ran out of control.
Turbo failure on the van, which had parked up on the side of the eastbound carriageway near the Holmbush Interchange in Shoreham, meant the engine was threatening to self-destruct.
Passing AA patrolman Phil Robinson spotted the problem and ran to the rescue.
He said: “I was just going past when I saw all the smoke and realised what the problem was.
“It was very dangerous as visibility was nil.
“The best way to stop a runaway engine (usually caused by turbo seal failure, which allows the engine to run uncontrolled on the engine oil) is to stall it, which is what I did.”
This meant engine speed was uncontrolled and, unless stopped, would cause the engine to blow itself to bits.
Switching off the engine does not stop it, as it is running on engine oil rather than diesel fuel – the van driver actually had the keys in his hand – and unless stopped, the engine literally self-destructs either due to mechanical failure or seizure through lack of lubrication.
It was pointed out by the AA that the smoke was also a serious risk to other motorists, as visibility was down to inches.
Mr Robinson is an AA patrolman from one of the Brighton-based patrols.
His on-board ‘dash-cam’ captured the video showing the van erupting in a plume of smoke around 10.20am.