1993 Volvo 850, Is intake heater necessary?

alexk243 · Post by **alexk243** » 02 Mar 2015, 22:40

So I have been reading around this site a lot and some people say its not needed, but a lot of people go through a lot of work to keep it functional. For those of us living in sub-zero winters is the heater hose on the airbox necessary? Or can it be removed with no issues?

Post by **taxi** » 03 Mar 2015, 03:46

Hi!
I'm in the process of finding exhaust leaks on my 2000 V70, and the first step (400 km ago) was to remove the heat shield along with the pipe to the airbox. We have had below zero temperatures and I have not noticed anything wrong yet. Nor does the car take more time to get to operating temperature.
My guess is it only uses heated air for the first few minutes.

Post by **abscate** » 03 Mar 2015, 03:55

Regulating the temperature of input air helps the car run most efficiently. I don't think it will cause damage but you might see an mpg hit in winter

Post by **Ozark Lee** » 03 Mar 2015, 07:10

I've never had any fuel economy issues after blocking the intake heater open, in fact it was quite the opposite.

The only problem I ever had was that the throttle body froze on a -10 degree (F) day when I was on the highway. It wasn't a real huge deal since I recognized what had happened. I just flipped the key back to kill the engine, shoved in the clutch, and coasted over the the side of the road where I could pump the accelerator a few time to free everything up. The residual heat from the engine unfroze it in under 30 seconds.

It was a fairly flat stretch of road and I was using the cruise control so the throttle body butterfly wasn't moving much at all for a 20 or 25 miles. Around town it never would have happened in the first place.

...Lee

Post by **scot850** » 03 Mar 2015, 11:54

I agree with the views on this. I don't think it is critical, just helps the engine warm up quicker. It would be nice to have on a turbo to help hopefully prevent the intercooler freezing while moving, but it wouldn't necessarily help on a cold start which is when I have tended to get the freeze problem up here most.

It will help a cold start, by warming the engine quicker and getting your cabin toasty potentially quicker, but essential, no.

Neil.

Post by **erikv11** » 03 Mar 2015, 12:58

With the flap stuck to the cold side, I had the throttle body freeze twice, also on the highway on the coldest days, like Lee mentioned. Because my wife drives that car on the highway, I use the heater in the winter then remove the hose and block the flap to the cold side in the other months.

So my two cents: Not essential, can be removed, there are possible issues to be aware of (frozen throttle plate, slower warm-up) so they can be accounted for.

alexk243 · Post by **alexk243** » 03 Mar 2015, 16:25

Wow, Didnt think about the throttle plate freezing up... Dont do much highway driving, but it does get cold enough here. I would have thought the residual heat from the engine would have taken care of that.

Post by **misha** » 03 Mar 2015, 16:51

I did mine few weeks ago.I have the later style airbox,vacuum and thermostat driven,like on s,v70.

When i apply a vacuum to it it's moving and when i apply heat with a hair dryer it settles in a half way from hot to cold.So it was not stuck on hot all the time.
Anyway i just screwed a long bolt which force it to cold only,all the time.I'll monitor how the car behaves and if i'm not satisfied i'll just remove the bolt and things will be like before.