View Full Version : I can hear a Turbo when engine off

03-06-2013, 12:39 AM
I hear a whine like a jet coming in from under the hood after stopping and turning the engine off.

I just started noticing this last week. Is this normal? If not, what may be the cause??

03-06-2013, 05:13 AM
Sounds like your van's Heater Booster, which takes a minute or two to shut down after you turn off the engine. It's basically a small diesel fired heater in the engine compartment behind the driver's side headlight that heats the coolant. This thread (http://sprinter-source.com/forum/showthread.php?t=628) provides a description of how it works. A small exhaust pipe exits near the driver's side front wheel well. It makes a cool jet engine sound when operating.

The center console button pictured in this post (http://sprinter-source.com/forum/showpost.php?p=2105&postcount=8) (same thread) is how you would turn it on and off.

I believe that it won't come on unless it is cold enough outside, and if you're normally in a relatively warm place that got cold recently, that may be why you're noticing it only now.

In cold weather, it can help your van's engine warm up much faster than without it, which means the cabin will get warmer faster too. In cold weather the diesel engine will take much longer to get warm than a gasoline engine.

03-06-2013, 12:22 PM
If your van is 2004, that might be pressure relief valve (like mine is doing the same noise). One of many posts about it:

Aqua Puttana
03-06-2013, 01:17 PM
Turbo John offers a good description of the diagnosis in this post.


He also gives a good R&R procedure in post 32 of the same thread.

I feel compelled to mention that there is a chance (0.1% :tongue:) that it may be your aux electric coolant pump which runs a bit after shutdown. vic

03-06-2013, 11:05 PM
Or it may be the A/C relieving pressure after shutdown.

03-06-2013, 11:48 PM
my "Espar" heater sounds that way?