Mechanics

VIBRATION NOISE WHEN CAR IS WARM AROUND

2003 Nissan Sentra

Noises problem
2003 Nissan Sentra 4 cyl Front Wheel Drive Manual 140000 miles

I have a loud vibration noise on my 2003 nissan sentra spec-v around 2000rpm when warm.

Does not matter if the car is stopped or moving,
in gear or out of gear.

Taken to 6 different mechanics, half say heat shields
the other half say internal inside my engine.

-So I start my car no noise
-I drive untill car warms up
-sitting in neutral rev car up to 3000rpm on rev-down
around 2000rpm car makes loud annoying vibration noise
-I can make the same noise driving around 2000rpm or just sitting there with foot on gas peddle
-car makes noise between 1900-2100rpm

+I have removed all heat sheilds noise still there
+I have a new engine in car with about 25000 miles on it
+taken it to master exhaust places they had there master tech listen to the car for about 2 hours with a stethoscopes and he claims noise is comming from oil pan or around that area
+Nissan master oregon tech who is one of the best techs on nissans in the country as nissan claims says its the exhuast sheilds I took them all off and I replaced hangers tightend bolts everything Nothing loose.

I dont think I left anything out but after spending 5000.00 for a new engine I am not so happy about choosing a nissan.
Avatar
Jcard503
March 27, 2010.




Hi jcard503,

Thank you for the donation and sorry to hear about the amount of time and $ that you have put into this.

Was the catalytic converter checked? Quite often the cat converter becomes detached internally and this would cause vibration noises.

Did this problem occurred immediately after replacement of the engine?

KHLow2008
Mar 27, 2010.
Yes it was hammered on by a rubber mallet no noise and I allready had the pre-cat problem happen to my engine.

And no it happened or noticed about 15,000 miles had been put on it

Tiny
Jcard503
Mar 27, 2010.
And wouldnt the cat make the sound all the time not just when warmed up after like 10min of driving?

Tiny
Jcard503
Mar 27, 2010.
The cat is subjected to high temperatures and when cold the parts could be snug. The heat can cause the internals to loosen up thus the noise.

When the noise occured, was the cat checked then?

KHLow2008
Mar 28, 2010.
Ok I will this time remove my cat and see if thats what it is but it has been hammered on several times

Tiny
Jcard503
Mar 28, 2010.
If it is engine internals, the noise should be present at all temperature conditions so I would suspect it to be external.

Let me know what you find.

KHLow2008
Mar 28, 2010.
K I took the cat off no pieces fell out. Looks and sounds solid.

Also wouldnt I hear the cat at all rpm's its very specific where you would not be able to make the sound unless shown how.

Also wouldnt the engine noise be heard once warm with the change in engine oil velocity?

I am kinda out of ideas. Its to the point where all mechanics are saying its internal and others saying extrenal. They said they will tear apart the engine and if it is the engine they will replace. And if its not the engine I need to pay for it.

Exhaust was my first guess to But the vibration noise is horable sounding
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Tiny
Jcard503
Mar 28, 2010.
For CAT noises, it can appear only at specific engine rpms.

Without the physical, it would not be possible to diagnose such noise problems.

You have a dilemma that is not going to be easy to resolve.

Engine internals should not cause vibration noise. Apart from the noise, is there any performance issues?

KHLow2008
Mar 28, 2010.
No problems at all thanks for all the help I do understand what you are saying

Tiny
Jcard503
Mar 28, 2010.
You're welcome and sorry for not being of much help to you.

Have a nice day.

KHLow2008
Mar 28, 2010.

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