Very smoky preheater

[mrzuckinihead]

Hi all,

As winter is now upon us (we live in Switzerland) our engine/cabin pre-heater on our 2007 D5 XC90 is kicking in sometimes.

But, its been super smokey. As in, point and stare, "your car is on fire" smokey. I don't remember it being this bad last winter either (including on any ski trips when it was properly cold).

This is not my video (https://www.youtube.com/watch?v=ZikbQPZse8E), and although it's not this bad, it's not far off!

It only kicks in when it's below 5 degrees C, but I find it a bit pointless - the car lives in a reasonably warm underground carpark, so the heater only activates for a few mins when we're on the road, before the car is warm enough.

Could it be that because it's only running for a short amount of time it's getting all clogged up/running too rich?

I'm not even sure what kind of heater it is - you can't activate it from inside the car, it only comes on when the main engine is started.

I'm tempted just to pull the fuse to save the hassle...

Any thoughts?

[SwissXC90]

I live in Switzerland too and also have the preheater, but I added the software to control it manually and to program it to come on at a preset time.

Basically, smokey preheaters are caused by them not being used enough

Run it for a while - as long as possible - to try and get it up to temperature and burn off some carbon
If that doesn't work, it needs stripping down and cleaning.

Don't disable it, it makes a huge difference in Winter to engine temp and thus emissions

PS:
If you are in canton Zürich or close by, I have VIDA and can run diagnostics on your car in exchange for a friendly chat and a beer

[mrzuckinihead]

Thanks very much for the VIDA offer - might just take you up on it! Every time I go anywhere near the Volvo garage I come back many thousands of Chuffs lighter...

We live in Basel, but travel around quite a bit, Zurich is not so far away!

Does the pre-heater actually do anything for the engine temp? I thought it was only to warm the cabin up? Or does it get the engine to temp quicker, and thus the cabin (if the cabin is from engine heat?)?

[SwissXC90]

Originally Posted by mrzuckinihead

We live in Basel, but travel around quite a bit, Zurich is not so far away!

Give me a bell any time.... I'll send you my mobile number via PM.

Originally Posted by mrzuckinihead

Does the pre-heater actually do anything for the engine temp? I thought it was only to warm the cabin up? Or does it get the engine to temp quicker, and thus the cabin (if the cabin is from engine heat?)?

The preheater heats the engine coolant, and circulates it with an electric pump.

If you have no programmable parking heater fitted (software only option, you have all the hardware already...), then this is all it does. Of course, it thus indirectly assists in warming the cabin quicker, as the cabin is warmed by the same engine coolant.
So the preheater's only job is to accelerate the engine warm up time to reach operating temperature quicker.

If you also have the programmable parking heater, like I do, it works like this:
1. First it heats the engine only.
2. Once the coolant has reached 30°C, it switches on the interior blower fan, and sets the heater dampers to blow warm air on the windscreen (to defrost) and into the feet area (to warm the cabin)
3. It switches off automatically if any of the following conditions occur:

• More than 1 hour has elapsed
• The battery voltage has fallen to a level that starts to jeopardize engine start
• The fuel level has fallen to a low level (It burns only 0.6L of fuel per hour, I think it shutsdown when about 10L of fuel is left in the tank)

I used my programmable parking heat last night:

From the dinner table in my friends apartment, I started the parking heater in the car via remote control 40min before I left the apartment
It was 0°C and snowing outside, my car had been parked for over 10 hours in 0°C conditions, the engine, coolant and interior were thus at ambient temperature: 0°C.
By the time I got to the car, after 40 min of preheater running, the interior was comfortably warm and the engine coolant was at 63°C - I know this from the CanBus Function Extender CFE that I have fitted.
My engine started easily, as it was at 63°C and I drove away in comfort and warmth. With no snow on the windscreen either. OK, it wasn't snowing that much, yet - but Friday this week it will snow all day...