Hi, so i bought this used celica GTS several months ago. phenomenal car...everything's in pretty good condition. Except i've noticed that the engine seems to make this diesel engine noise when revving under 3k rpm for gears 2 and up unless i accelerate SUPER slowly.
It makes the sound in 1st gear until like 1500 rpm also.
The sound's been progressively getting worse.
i've done an oil change (mobil 1 synthetic extended) w/ mobil 1 filter, and seafoam. I don't know if it always sounded like that because maybe i was too excited and didn't notice before. But i don't remember hearing anything like that. It first started sometimes, and now it does it almost frequently. But it's also weird because sometimes it doesn't make the sound at all.
Anything above 3k rpm and it sounds normal.
Thanks!