Help, Car Makes A Thud Noise When Starting Up

[SL33K]

Hi guys, don't know if any one has experienced this but when i start my car i get a thud or knock under the car.

this sound only comes when i start the car the first time. and sometimes it wont come on start up too.

cant figure out what it is.

any help will be appreciated.

cheers.

[blk94r33]

Haven't changed the exhaust recently?

[sonicii]

I'm thinking the same thing. Exhaust or strut tower brace. Other than that.. a broken engine mount?

[tienscissors]

Does it occur as you turn the key to start the engine? or after the engine has already started?

Long shot, but could it be the ABS brakes checking? It usually occurs when you first start driving though so might not be it.

[SL33K]

It happens when the engine turns over. but sometimes its not there.

No noise after that, the car revs fine and is very quiet.

How do i check a broken engine mount? is it an easy fix? don't know much bout these things.

I just bought the car recently. not sure if anything was changed.

[SL33K]

I dont think it is the ABS, is the ABS sound the sound that comes when i reach about 10kms? i hear that and read that most v owners hear the sound around that speed the first time the car is started.