I'd drain the oil and see how much you really have ..... (taking into account the 2L you put in ) ... if you've got plenty then the symptoms may be due to a major overheat caused by your split pipe. If you have not much more than your 2L and you haven't had pools of oil on your garage floor I'd suspect a leak from something like a feed to the oil pressure gauge that's fed under pressure when you're running (either that or at the service they put a bit in and forgot to go back and fill the rest ... if they'd just drained it and forgotten altogether I doubt it would have made it to 600 miles) .... either way what you describe doesn't sound good for your engine unless you've been very lucky.
K
Ps .... sorry, I tend to approach everything from a 'do it yourselfer' viewpoint ..... depending on how long the 600 miles has taken maybe you should trailer it back to whoever serviced it and stand over them while they drain out the oil .... if there's not much more than your 2L and they can't point to a very serious oil leak then they have some questions to answer
Last edited by Image; 19/10/20 02:44 PM.