The Merc 500 SL

After eight long years of fruitless fettling, the Mercedes 500 SL has finally deigned to run properly and has emerged, blinking, into the light with a fresh MoT and only a mild list of advisories – the automotive equivalent of a retired racehorse being declared “sound enough to walk to the pub.” This particular beast, my beloved R129, boasts a glorious 5-litre V8 that once purred like a panther but for most of the last decade has spluttered more like a damp lawnmower.

Back in 2017, in a fit of naïve optimism, I handed it over to the first garage. They had it for three years. Three. Entire. Years. That’s not a repair – that’s a custody battle. I suspect they occasionally poked it with a stick, but actual progress was limited to vague mutterings and large invoices. Eventually, I retrieved it, still misfiring like a knackered jazz band and, after a hiatus, dropped it off at the second garage – Paul’s.

Now, Paul’s a good bloke and knows his way around an engine bay, but because I was on mates’ rates, the SL was permanently shunted to the back of the queue, behind paying customers and passing tumbleweed. He’s had it for over three years. I half expected to find ivy growing through the wheels when I went to pick it up. But lo – he finally declared it fixed and handed me the keys with the air of someone bestowing a newborn child.

I made it exactly twenty minutes down the road before the misfire returned like an unwelcome relative. But Paul had a theory. “Fill the tank,” he said. “Right up to the top.” I raised an eyebrow. This sounded less like mechanical advice and more like folk medicine. But I did as instructed, and – I kid you not – the misfire disappeared. It seems my SL has developed a taste for abundance. Paul opined that the new fuel injectors and the crap in the bottom of the tank was to blame and it simply needed flushing out.

There are a few fresh scratches, of course, that definitely weren’t there before – presumably garage staff performing interpretive dance across the bonnet – but I didn’t even flinch. The bottom half of the car already looked like it had done a tour of Afghanistan, and the hardtop’s finish was more faded than a 1970s sitcom. Fortunately, I know a brilliant Romanian sprayer who’ll make it look like new. Then it’ll be handed over to another Romanian I know who valets like he’s detailing the Crown Jewels. Both work at the place I drive for. Between the two of them, the SL will be showroom-fresh – or at least no longer resembling an abandoned council skip.

The oil light, meanwhile, is permanently illuminated, despite the engine being positively brimming with the stuff. I’ve checked. Obsessively. The fuel gauge refuses to show more than a quarter full, without ever troubling itself with accuracy. Occasionally, for reasons known only to Stuttgart and the spirit world, it lurches into ASR mode – traction control kicking in when I’m coasting gently along at 30, with not a hint of wheelspin or drama. It’s like being shouted at for a crime you haven’t committed.

But the real villain of this saga was the wiring loom. Mercedes, in a moment of green-tinged lunacy, decided that biodegradable insulation was the way forward. Which is all very noble until you realise that cars aren’t supposed to rot from the inside. Over time, the loom imperceptibly disintegrated, shorting wires and resulting in the mystery misfire. Diagnosing anything was impossible – the car was basically screaming in binary.

The solution? A brand-new bespoke loom, flown in from Germany, no doubt hand-crafted by precision-obsessed engineers named Uwe. It’s sorted the lot. The misfire is gone. The gremlins have buggered off. The V8 roars once more, and for the first time in years, the 500 SL behaves like a car rather than a haunted toaster.

So yes, it’s still got quirks. But it’s back on the road. It’s mine. And it runs. Which, after everything, feels like nothing short of a resurrection. And if it ever misbehaves again, I’ll brim the tank, mutter something vaguely Teutonic, and hope Paul hasn’t changed his number.

I'll get to fully sorted, drive it for the summer (attending a few classic car shows) and then sell it to fund the restoration of the Triumph GT6 which, according to Paul, would benefit more from a supercharger on the existing 2 litre straight 6, rather than a full-blown transplant of a Mazda 1.8 turbo engine.