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Hi guys,

I get a loud crunch for about 1-2 sec everytime i start the engine and also loud tapping sound (sounds like pistons) when i first start my car in the cold morning. Now if i was to warm the car up, take it for a drive then turn the engine off to start it back up again to look for the sound, the sounds gone away due to it being warmed up. Hence, why is the reason i can't take it to any mechanic to show the issue. :domokun:

Ive only noticed this loud crunch for 1-2 on cold start after ive changed my oil to 'Elf Synthetic Oil 10W50'. This is pretty much all the relevant information i can provide from my knowledge, and also that the sound is coming from under the hood on the passengers side, kinda sounds like its coming from the head area on the passengers side where the turbo is and all.

Could it be that im using a real thick oil, hence is why its making weird noises on cold start till its warmed up?

Note: The crunch sound is only for about 1-2 sec on cold start and not constant whilst idling in cold or driving.

Much appreciated for any helpful response.

Edited by R33Turbo
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thanks alot for the input man. maybe it is the starter motor! how much is it to replace? or repair? aproximately? is it still driveable (as the sound goes away)?

Also i get louder engine ticking sound especially in the morning rather than when it was warmed up? could that be related?

I wouldn't wait too long to get it checked, if it is infact the issue and it's disengaging either slowly or not at all it will be spinning at higher revs than it's designed to for longer than it's designed to, the starter gear could shatter or lockup causing damage to your flywheel ect.

Starter motors use centrifugal force and a grooved shaft to throw out the gear, it could be clogged up and only need a clean or you may have to get it repaired or exchanged. You'll have to call around locally for an idea of availability & price. Auto elec places ect...or get a wrecker one.

It's not a huge issue or costly, so I do hope you find it to be the cause.

Edited by madbung

Could be an indication it's clogged up with grease/grime/oil ect when it absorbs the heat from use/engine it could free it up somewhat.

Then when it cools it sets again again...so to speak.

Get it checked out either way.

i've got the EXACT same problem, i'll have to check the starter motor

i think it may be the thickness of the engine oil we're using...maybe its just too thick! try thinner oil and let me know cuz my service is another 4000km away :)

Absolute rubbish, re: oil thickness...If someone can say why running thicker oil will make a grinding crunching mechanical noise on start pls share.

Thicker oil takes longer to fill lifters ect on start up so you'll get an extended tappet type noise until they fill up thats all.

It can not make grinding or crunching sounds, it's oil !!....thats the noise mechanical problems make.

This forum is becoming rife with bad advice..

Edited by madbung

Funny this. I've got excatly the same problem, clutch is in its last days and I get that crunching sound on cold start.

I've been suspecting the starter motor.

OH!!!

Yep well ive got a close answer now....

its definitely my 'starter motor' and its due to my clutch going ! (starter motor may be covered with clutch dust and seizing up)

  • 2 weeks later...

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