engine noise but cant find it!?!

[ptaroni]

after posting up about play in the balance shaft, it appears it only got a bit of play where it meshes into the oil pump drive or something on them lines.. timing belt tensioners are all ok, balance shaft timing is all ok and tension is good. removed all the conrod bearing caps again to double check and they are all ok. really getting to me that i cannot find anything that would cause a knocking noise i have got... it only happens when you rev the engine slightly under a bit of load, causes no loss of power and not metal filings etc in the sump... if anyone has any other ideas then post them up please, ill check anything! if by after the weekend i have still found nothing then i will remove the engine and have it fully checked and rebuilt with forged internals, just means ill be without my evo for a month or two and be driving a fiat punto thanks again!

 

[Wingnut247]

Try removing the auxiliary belt and run it to see if noise is still there! If no noise then its got to be a problem with alternator, power steering pump, aircon pump or something else aux belt runs! Had a similar noise which turned out to be alternator pulley loose on alternator shaft even though nut was tight!

 

[ptaroni]

Ill get the sump back on tonight and run it up at the weekend! Really starting to puzzle me now! Thanks for the reply

 

[kobe_1201]

any updates on this lad?

 

[ptaroni]

nope, put the sump back on yesterday changed oil and filter, ran it with no aux belt on and still the same! ive noticed that cylinder 4 has a fouled up plug upon running it up yesterday, piston looks quite damp too, but it does not misfire?! swapped round coilpacks and swapped plug and ran it up again and same cylinder 4 so something is not right. will get a bore scope from work tomorrow and have a look but when i had the sump off, what i could see of the bores there was no damage/scores. anyone had any problems with fuel injectors? im thinking now maybe i have a leaky one and flooding the cylinder? just another thought...

 

[ptaroni]

Just an update, removed and stripped the engine and cylinder 4 piston has melted! Wasnt expecting to.find it but am.fully forging it so no biggie! Hasnt scored the bore just left a bit of.piston melted to the top of the bore but a rebore to 86mm will be fine . Also whilst the engine is in bits i looked at some parts to see what i have, the turbo is a td05, 10.5t and the cams are crower 64433.2s which i have read up they are for an evo 8 and stage 3. The exhaust manifold is not standard either. .. im beginning to think that it may have been.caused by not having the engine mapped to suit the mods. Any thoughts ?? Thanks