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05 CDI engine noise is super loud when below 30°f.

667 views 2 replies 2 participants last post by  Rossafuss 
#1 ·
Not sure if this is normal or not, it's done this since I bought the car over a year ago.

When it's below 30° outside and the car has sat overnight, until the car has warmed up, the engine noise is REALLY loud under acceleration. It's not unusual noise, no clanking or knocking or anything like that. It's the normal sound of the engine, just really loud. It isn't any louder than normal at idle either.
Does anyone else's CDI do this?

Car has 420k miles, not sure if it's maybe milage related, like maybe a stretched timing chain?
I'm not sure.
When the engine is warmed up, or if it's warming up in warmer weather, the car sounds super quiet under acceleration.

Also, the car is still super smooth when it's doing this as well. No vibrations, no unusual shifting, nothing like that. It's ONLY the loud engine noise.

Let me know what you guys think, if this is normal or somthing I should be investigating.
 
#2 ·
420,000 miles on a 2005? Must've been a taxi or a traveling businessman's car!

My Diesel pickup truck does something similar, but in my case, it's also at idle. Generally, when Diesel engines are cold, they're noisy. When the engine gets warmed up (takes a few minutes 'cause the engine's 1,100 pounds), it becomes much, much smoother.

From your description, it could also be the pilot injection getting turned off when the engine's very cold. Again, my truck does this. Pilot injection is what makes more modern Diesels sound quieter than in years past.

Working on finding an E320 CDI of my own.
 
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#3 ·
I'm the second owner of the car. The previous owner was a self employed marketing guy! Drove all over the country! He put just shy of 400k on the car.
If it wasn't for the odometer, you wouldn't have a single CLUE the car had more than 150k on it. It's beautiful and smooth as butter.

That makes sense, I heard something about the piliot injecting being turned off when the car is warming up.
I just didn't know what was normal, as I've never driven another CDI in the winter time.
Like I said, it quiets down alot when it warms up.
I just wanted to be sure. Can't be too careful when you have over 400K on the original engine and tranny. :p
 
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