Hi My 16v has developed a strange screeching noise. Immediate thoughts were the distributor as it sounds like a rotational noise coming from the gearbox side of the engine, topside. I have just fitted a newly reconditioned Bosch dizzy and the noise is still there (albeit it now idles a lot smoother so one improvement!) Done approx 2000 miles since install with zero issues until now. A link to video showing the noise: It only starts doing it when the engine is hot and has no effect on how it performs/drives. Any thoughts? Thank you.
Sounds like an air leak? Or Could it be the thin steel plate between block and bell housing, rubbing on the flywheel?
Alternator bearings/brushes? Could get it up to temp stop remove the belt then run it for a few seconds eliminating the belt, alternator and water pump. Caution! Without the water pump several seconds only!
I agree with Rustbuster and reckon that’s the alternator or worst case the water pump but I’d put money on the alternator bearings. As well as the bearings check the mounts, in case there’s misalignment. This happened on my E28 - got new bushings and bolts - good as new after that.
Thanks for the suggestions. I have another ISV to try and will check the associated pipework when removing. And also eliminate the alternator with a brief belt removal. will report back
Fitted a spare ISV yesterday and found a small split in the rubber Y pipe that connects on the bottom of the valve! Luckily I had a spare one of those too so refitted and so far so good, no screeching noise. Not sure how good my 'spare' Idle valve is though as it struggles to keep it running on start up/cold. I may put the original ISV back with the new pipe and try that. Thank you Toyotec for pointing me there
