Thread: Loud At Idle
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Old 02-08-2013, 12:23 PM
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Quote:
Originally Posted by Jareb View Post
Thanks D911.....I'll pull the injectors and have a look. So, if the injectors were old and worn, would this cause a louder than normal idle that smoothes out with a small rpm increase?
I'm not worried that something is seriously wrong with the car because it runs and drives so well, but I know what it is supposed to sound like at idle and it just has TOO much of a diesel sound if you know what I'm trying to say. Has me curious about the injectors or other possible causes
Thanks
John
Like I said you can pull one Injector and get some idea about them. Below is a pic; look directly in the center of the Nozzle and you will see the tiny drilled passage. There is that one and then further up in the Pintel is a larger passage drilled acrossed the Pintel.

My own belief is that once the passages are plugged solid a Diesel Purge is not going to get the Carbon out.
In the Manual the show picking out the holes with the correct sized Music Wire in a Pin vise. In a Fuel Injection Shop they would be a canidate for the Ultrasonic Cleaning Tank.

In this pic if the Black area around the Pintel is burned away or erroded; especially if that goes all the way to the Pintel; is a sign the Injectors have been in there a long time.

It is not the only thing that can cause that. I thought I mentioned the Timing Chain Stretch effecting the Valve Timing and also there is the Fuel Injection Pump Timing.

Concerning the Fuel Injection Pump timing. The timing can cause it to nail if it is too retarded/late and also if it is too advanced.

Now that I think of it low Injector pop/opening pressures can cause nailing if it is so low as to badly effect the ability to atomize the Fuel.
Attached Thumbnails
Loud At Idle-injector-nozzle-central-hole-feb-13.jpg  
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