John Joseph Lydon, the singer better known as Johnny Rotten, lives in a ramshackle brick house next to Venice Pier in Los Angeles, which is where a lot of very eccentric people tend to hang out and is therefore one of the few places in the Western world where he might actually blend in.

So the plan is to meet for lunch at a local Cuban restaurant before venturing outside so that the photographer can take him doing his punk rocker thing among the beach bums, tramps, drug dealers, street performers, artists and fashionably-dishevelled millionaires who inhabit this most diverse of LA's urban neighbourhoods.

That's the plan, at least. But when Robert the photographer turns up, two hours into what has so far been a perfectly amiable and wide-ranging chat about John's life, times, and forthcoming UK tour with Public Image Ltd – the band he formed after the Sex Pistols self-destructed in 1978 – the mood suddenly turns. First, John tells my colleague to "fuck off". Then he belches, lights a cigarette, and announces, with regard to the photo-shoot we had so meticulously planned, that he now won't be playing ball. "I'm just not into this," are his exact words. "In fact, I couldn't care less."

The problem, it turns out, is one of logistics. At the age of 54, John keeps to a strict daily regime, part of which involves liquid-only lunches. Today, that liquid has been Corona, a beer he describes as "Mexican piss" but actually adores, especially when it's served with a slice of lime he can chew ferociously, spit into his hand, and deposit on the table with a flourish. After five bottles of the amber nectar – his only mind-altering pleasure now he's grown out of Class As – he'd like to carry on boozing. "The only way you'll get me to leave this place is if I can walk around with a beer," he says. "But in this country, they arrest you for drinking on the street. So I'm not going anywhere."

I won't argue. Not with the man who cut a snarling swathe through the early years of the punk revolution, and for a brief period of the late 1970s was the most outrageous, volatile, and downright dangerous human specimen on the planet. Not with a walking exclamation mark whose very existence has, at various moments during the past 35 years, upset church groups, politicians, monarchists, mothers, half the music industry, and pretty much anyone in Britain who happens to sport a non-ironic moustache.

John may be careering gently through middle-age, but he's still an angry young punk at heart, with a bog-brush haircut (shaved back and sides, unwashed and longer on top), four big earrings, and an enduring reputation for both spitting venom at and punching people who upset him. In fact, he's just devoted several minutes to explaining that the philosophy he applies to both his life and music can be defined by a single line from Public Image's shouty old hit, "Rise". To wit: "anger is an energy". So I'll leave him well alone.

Robert the photographer is a braver man than I, though. He comes up with a cunning plan. A compromise, if you will: we'll order two more bottles of "Mexican piss" for John, and then (here's the ingenious bit) pour them into a large metal water flask which he just happens to be carrying in his equipment bag. That way, our thirsty former Sex Pistol will be able to walk through Venice, boozing in secret. Passing cops will have no idea that he is quietly breaking America's zealously-enforced drinking laws. How's about that for an act of rebellion? "Ooh, you cheeky monkeys!" John smiles. "I think you've won me over." And with that, we hit the streets.

Like any combustible material, John needs to be handled carefully. In a sunny mood, he's delightful: alternately over-excited, animated, and hilariously disgruntled. He still brims with the manic energy of old, but age has softened a few rough edges, and in his white linen suit and steel toe-capped Doc Martens, he looks somehow more kindly than the grubby enfant terrible who created a genre of music based on a sort of angry shouting. Even the horrible dentistry which inspired his nickname is gone, save for one large gap in his upper jaw. "I had all my teeth done, a few years back, but then I smashed this one open with a fucking cherry stone," he explains. "Cracked it, swallowed it, and then went to the dentist, who advised me to search my poo for it. I told him, 'No fucking way is that going back in my mouth, dear!' So now I've got a gap in my teeth, right at the front." On the plus side, the gap is exactly the right size to hold one of the cigarettes he chain smokes.

John has lived in Venice with his wife Nora ("the best thing the world has ever made") since the 1980s, when he quit the UK because the police kept raiding their London home in search of drugs. He had been convicted, once, of possessing amphetamine sulphate, which he liked "because it was illegal and allowed me to get more done". They own another house in Malibu, where they drive at weekends in a yellow Volvo, and a yacht, which they keep moored in the local marina.

On a normal day, John rises at dawn, eats "two fried eggs for brekker" and potters around listening to music. The contents of a vast and varied record collection are a state secret, because he hates other artists to know he likes them. But he does reveal that it is made up entirely of vinyl. The MP3 revolution passed him by, as did the internet, which he "used to use for porn" but now avoids altogether, even eschewing it in favour of fax machines. In Malibu, he'll while away the afternoon swimming in his pool. In Venice, he'll hit local bars. And he's also fond of gardening: "I grow bougainvillea and jasmine, mostly – things that bring in the hummingbirds."

It's an idyllic existence, somewhat bourgeois, and therefore quite at odds with almost everything he once stood for. The only problem with his way of life, he says, is that his reputation means he gets routinely searched at customs and immigration "by men who want to look up my bottom", whenever he returns home via Heathrow.

John's bottom is about to be searched once more. On Monday, PiL (as he calls Public Image Ltd) begins a week-long tour of the UK. It's their second in the past 12 months, and follows a 16-year hiatus in which John widened his career portfolio by briefly reforming the Sex Pistols, and appearing on a selection of reality TV shows, including I'm a Celebrity ... Get Me Out of Here!, where he famously said the c-word to a bemused Ant & Dec, on live TV. He also made documentaries about insects and sharks, which fascinate him, for the Discovery Channel, and starred in a TV advert for Country Life butter, in which he dressed up in tweeds in a nod to his latter-day image as a national treasure.

Did I say national treasure? Oops. "National treasure?" he responds, once more sounding worryingly combative. "Those words are just a logo. They are used to bring you down. People call me 'national treasure' to find if there's a conceit in me. And I don't need it. I don't need a fucking knighthood either, by the way." As you wish, I reply. Perhaps I should let Her Majesty know. This kick-starts a discussion about the Royal family's decline into what John describes as a "Disneyland attraction". That process, he says, can be directly traced back to the Sex Pistols, whose "God Save the Queen" was considered moustache-twitchingly outrageous 30 years ago, but now seems quaintly dated.

This week's tour will mark John's first visit to the UK since the death of Malcolm McLaren, another man who has been called a national treasure. McLaren was of course the impresario who, in 1975, "discovered" John striding down London's King's Road in a T-shirt that proclaimed "I HATE PINK FLOYD". The story goes that, after asking him to audition for a new band he was creating, McLaren watched the 19-year-old Lydon deliver an entirely note-less but passionate rendition of "I'm Eighteen" by Alice Cooper, using a shower head instead of a microphone, and signed him up, on the spot. That group became the Sex Pistols. And the rest is history.

When McLaren died in April, John issued a short tribute, via his PR man. "For me Malc was always entertaining, and I hope you remember that," it read. "Above all else he was an entertainer and I will miss him, and so should you." The comments represented a posthumous burying of the hatchet, since the duo had often fallen out, over the years, most notably when Lydon quit the Pistols in 1978 during a series of ugly disputes that culminated in a disastrous tour of the US that saw Sid Vicious, the band's bassist, stab his girlfriend Nancy to death before committing suicide by way of a heroin overdose.

I ask John if he plans to take the opportunity, during the visit to Britain, to properly pay his respects to his old friend? "Pay my respects?" he replies. "Why would I want to do that?"

Then his face lights up. A long anecdote, of the rambling sort John is in the habit of launching, when you get him going, begins. "Bob Geldof told me an interesting thing about Malcolm's funeral, actually," he says. "He came to one of the gigs I did in Canada, and when we were talking afterwards he told me, 'You didn't miss much... It was the usual fiasco.' Apparently Bernie Rhodes [the former manager of the Clash] and Vivienne Westwood were up there arguing at the altar, during the sermon. And the crowd was full of all the usual wannabees." He chuckles. "Poor old Malcolm: they gave him a really lousy send-off!"

John didn't attend McClaren's funeral in person because, frankly, he couldn't be bothered. "I'm still really upset about my dad's death [his father, John, passed away two years ago], and not that upset about Malcolm's," he says. "I'd be lying if I pretended otherwise. Yes, I miss him, but not for any logical reason other than that he was a good bloke to have a row with. Other than that he just tried to manipulate me. And later on, the self-aggrandisement of the man became a real problem. He loved to put all his success down to his own genius, but Malcolm was a man who lived on the coat tails of others. And he lacked commitment, really. I never knew him to finish anything he started. Including running for Lord Mayor of London – he made a right old bollocks of that."

The person who made John famous isn't the only former colleague to have acrimoniously parted company with him. There have been more than 40 members of PiL in its three-decade history. Many found working with a man who could start an argument in an empty room a wee bit challenging. But these days, John claims to be mellower. His current band-mates, for example, have put up with him for almost a year. They are Lu Edmonds, a former guitarist for The Damned, Bruce Smith, who played drums for the Slits, and Scott Firth, who in a distant incarnation collaborated with both Elvis Costello and the Spice Girls. It's a strange mix, on paper, and much like Lydon's music, it can be hit and miss, but somehow works.

"I've always said, over the years, that my body and mind is the Sex Pistols, but my heart and soul is PiL," John says. "I still believe that. And to be honest, I genuinely enjoy what we're doing now. I think this is the best PiL format I've ever, ever worked with. It's the one that makes the most sense to me. We completely understand each other, on rehearsal and on stage, to an amazing degree. When we perform, it creates some wonderful virtuosity moments." Their comeback tour, at the end of last year, was well reviewed. This newspaper gave it four stars, praising John's "rare emotional drama, drawn from music and memories he can't ever fake". Our critic added: "His vocal extremism, from a pure howl down to soft contemplation is just as remarkable."

John is particularly proud of PiL's influence, which extends across several musical genres. Though its back catalogue has been patchy, it is no exaggeration to say that without PiL albums such as The Metal Box, and songs like "Rise", we would never have had bands like Massive Attack. The same goes for the Prodigy and Red Hot Chili Peppers, John says, "though of course, people never fucking give me credit". It's proof that his legacy extends way beyond punk, a genre he now regards as creatively bankrupt.

"Look what punk has ended up with: Green Day," he announces. "Is that my fault? These wankers, who can pack out huge auditoriums, but are completely vacuous? Musicians who are nothing more than coat-hangers: manufactured from top to bottom. I'm offended by the things they do. I view them as something like arthritis. They say they're so punk and anti-corporations that they travel around in their own ice-cream van. Well that's bollocks. I know for a fact that it's all private jets."

No one delivers a rambling put-down quite like John. He doesn't just do it behind people's backs, either. A couple of years back, he ran into Green Day at a fashion party in New York organised by Anna Wintour. And he dutifully let rip to their faces.

"Jamie Oliver and Green Day came walking down the corridor at the same time," he recalls. "And I really let them have it. Oliver first, for being a mockney. He got all upset and told me I was letting the side down. Then Green Day, who I shouted at for a while. A few minutes later, Richard Gere comes up to me. He says, 'Well done John, they needed telling off.' I replied: 'OK, hamster boy!' Now that to me was a good night out."

Other good nights out, if you like public rudeness, have in recent years included the Mojo awards in 2008, when John had an argument with the Welsh singer Duffy and made her cry, and the Summercase Festival a few months later, when Kele Okereke, the frontman of Bloc Party, claimed to have had a fight with him ("he had an album coming out, and totally fabricated the incident," John claims). At the Q awards, he booed Damon Albarn, called presenter Johnny Vegas "Teletubby", described the entire audience as "posh bastards", and used an acceptance speech to dub Kate Bush "fucking brilliant".

These skirmishes have extended John's career, keeping the old agitator in the papers, and making him still seem relevant. The big question, though, has always been whether he really believes what he says, or whether his energetic anger is part of an act. Was Johnny Rotten a real person, or a pantomime caricature, created to scandalise Middle England and sell records to a disaffected youth in a now-bygone era?

A couple of hours in John's company isn't enough time to be quite sure. At times, he will contradict himself, sometimes quite shamelessly. Every now and then, you get the impression that his controversialism is a bit forced, that he's going through the motions, being rude for effect. But at the same time, there is nothing fake about where he came from. He was born on 31 January, 1956 to decent, hard-working Irish immigrants who inhabited a two-room house, which might nowadays be called a rat-infested slum, in London's Finsbury Park. Aged seven, he fell ill with spinal meningitis which kept him bed-bound for a year, and resulted in the hunched shoulders and slightly awkward stare for which he became famed. He was later thrown out of school. The angry young teenager who exploded on the scene in the late Seventies was the real deal.

Neither was there anything fake about the way the Sex Pistols went on to capture the spirit of their times. On paper, they were not exactly great musicians, at least in the traditional sense. John didn't play an instrument. He screamed and shouted rather than sang. He had no coherent set of beliefs, except anger and acrimony. But he nonetheless ignited a generation. Neither, of course, could the mess of Sid's death be dismissed as an elaborate publicity stunt.

What I do know, having hung out with him for an afternoon, is that he's still always spoiling for a fight. As we're about to say our goodbyes, he pulls a sheaf of faxes out of his pocket. They are complaints, e-mailed to his manager, John "Rambo" Stevens, who lives in Arkansas, complaining that PiL will shortly be performing in Israel. One, from a fan called Lawrence Casin, declares: "I will destroy all my albums and paraphernalia that I have collected over the years if you bastards play that hell hole."

Most musicians, particularly those who have been around for 30 years, wouldn't let hate mail upset them. They probably wouldn't even read it. But John's anger is genuine. He wants me to record it, for posterity. "I really resent the presumption that I'm going there to play to right-wing Nazi jews," he tells me. "If Elvis-fucking-Costello wants to pull out of a gig in Israel because he's suddenly got this compassion for Palestinians, then good on him. But I have absolutely one rule, right? Until I see an Arab country, a Muslim country, with a democracy, I won't understand how anyone can have a problem with how they're treated."

That's our Johnny Rotten. Always lively. Always entertaining. Often wrong. But, whatever you may think of him, never afraid to stick that bog-brush haircut exuberantly over the parapet.

A classic UK punk playlist

1. Crass "Do They Owe Us a Living" (1978)

2. Killjoys "Johnny Won't Get to Heaven" (1977)

3. Television Personalities "Part Time Punks" (1978)

4. Johnny Moped "Darling Let's Have Another Baby" (1978)

5. Desperate Bicycles "Smokescreen" (1977)

6. Subway Sect "Nobody's Scared" (1978)

7. Crisis "UK '78" (1979)

8. Swell Maps "Let's build a Car" (1979)

9. Sham 69 "What Have We Got" (1977)

10. Automatics "When the Tanks Roll Over Poland Again" (1978)

Chosen by Sean Forbes, Rough Trade Shops, London