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2004 GXP getting loud

Old 04-14-2013, 07:32 PM
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Default 2004 GXP getting loud

Its been a while since I had any issues with my car but my luck ran out within the last month .

I have noticed that the car is getting quite loud. Normally I wouldn't mind, but I know that with the louder sound there is a problem. To me it sounded like there might be a problem with the exhaust system.

I took it to my mechanic for its bi annual check up and we ran it and he couldn't find any exhaust leaks. He said there would be a hissing sound or ticking sound and should be able to visually detect the leak or feel the exhaust leak.

It only seems to be louder under load. If I am slowly accelerating. If I was to put my foot into it you wouldn't notice the difference.

The other thing I noticed is that every once the car will stall when manoeuvering at slow speeds.

I have no idea if these two are related.

There are no lights so I can only assume there are no codes.

I have been vigilant with maintenance. Had the plugs changed 20k miles ago.

It now has 77 000 miles on it.

Any suggestions???
Old 04-14-2013, 08:33 PM
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Inspect the hose from the air filter box to the throttle body to see if it is cracked, broken, or disconnected.
Old 04-15-2013, 02:26 PM
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Originally Posted by 2kg4u
Inspect the hose from the air filter box to the throttle body to see if it is cracked, broken, or disconnected.
Checked that out this morning and it is fine.
Old 04-15-2013, 03:03 PM
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Kind of hard for us to diagnose a noise based on a description posted in the forum when your mechanic can't tell what it is when examining the car.

Do you hear anything unusual with the hood open and the engine running? Where do you think the sound is coming from?
Old 04-15-2013, 09:48 PM
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Originally Posted by 2kg4u
Kind of hard for us to diagnose a noise based on a description posted in the forum when your mechanic can't tell what it is when examining the car.

Do you hear anything unusual with the hood open and the engine running? Where do you think the sound is coming from?
Agreed. It is kind of hard. I notice the difference. The wife notices the difference but people who don't drive it wont notice the difference.

Nothing unusual under the hood when running
Old 04-16-2013, 04:53 PM
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Does it happen when the engine is cold, or only after it warms up?
Old 04-20-2013, 08:31 AM
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Originally Posted by 2kg4u
Does it happen when the engine is cold, or only after it warms up?
It makes the noise all the time. The sound is similar to when it is -40 out. The difference is now when it warms up the noise doesnt go away.
Old 04-23-2013, 09:39 PM
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What does the noise sound like? Is it a fast ticking sound? A slower rapping noise from the engine? Try to make a short video and put on Youtube, then add a link to here.
Old 04-23-2013, 09:43 PM
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The pistons are made from a alloy that contract slightly in the cold or when the engine is cold. You will get a slight rapping sound when cold. When they heat up, they expand to close the clearances between them and the cylinder wall. Try doing a compression check. You may have cracked a piston or broken a ring. Not set in stone, but just a thought.
Old 04-24-2013, 04:46 PM
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I spent an hour underneath my car yesterday looking over the exhaust the best I could and I could find nothing. Then it dawned on me recently when I was driving there was a bit of a clunk when switching from 1st to 2nd gear. I put on the emergency brake and put her into drive. As it turns out the motor moved way more than it should. I have been down this road once before but it never made the noise it is now. Hopefully the exhaust system hasn't been damaged by the engine flopping around. Hopefully it is just the vibration.

I also noticed that there is quite a bit of leakage from the oil pan and valve cover on the rear of the engine. I figured I would get this all taken care of while the sub frame is out.

My mechanic (retired) said he would pass on tackling the job so I got an estimate from GM. They want $1800 for these repairs. (Ouch).

I located Northstar Performance which is only about an hour from where I live. They will pull the engine and replace the head gaskets, new improved studs, valve cover gaskets, water pump gasket, cross over valve gaskets, front and rear engine gaskets and oil pan gasket for a flat fee of $2500. To me that makes more sense.

Now I just have to decide if I get the car fixed or do I fix the motor mount get rid of it an move on ??

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