Aux air valve

Post by **RandomHero** » 13 Mar 2006 11:13 pm

Does somebody know the correct working order of the aux air vavle. It's the thing mounted aside the valve cover.

On the picture under the second V in Volvo on the valve cover, with the white connector on it:

This valve is connected in the hose between the little pipe on the following picture and an other pipe above the cold start injector. It has defenately something to do with the amount of airflow to the cold start injector. But does someone know the exact way it works?

Post by **pettaw** » 14 Mar 2006 10:58 pm

Aux air valve is basically like a throttle stop on the chokes of carb cars, its a bypass that effectively opens the throttle a bit to raise the revs/stop the engine stalling when its cold.

It works in two ways, ambient temperature, cooler and it opens more, and also there is a small 12V heater to shut the valve after about 5 minutes even if the valve body doesn't get warm.

The cold start injector is separate and is fed by a seperate circuit.

Hope that helps.

Post by **RandomHero** » 14 Mar 2006 11:39 pm

Thanks a lot, that help me indeed.

I was thinking about it last night after posting and came up with the same way of working. Is it also that when more fuel gets injected there must be more air to get the right mixture, otherwise the extra fuel from the cold start injector won't help?

Post by **foggyjames** » 21 Mar 2006 01:22 am

I'm pretty sure the two things in the first picture are to do with Pulsair, rather than the aux air valve....I'm not 100% sure on a 360 (ironically!), but on 7/900s the AAV sits beneath the inlet manifold.

cheers

James

Post by **pettaw** » 21 Mar 2006 03:48 am

No the cold start injector has nothing to do with it. The aux air valve has nothing to do with it. All it does is effectively open the throttle partially. It is bolted onto the valve cover on 360s. silly place cos it doesn't get engine heat, but luckily the 12V supply to the internal heater takes care of that.

The cold start injector works on a timed circuit and only fires whilst the starter is running to richen the mixture enough to get the engine to fire from cold. The car would start and run perfectly without the aux air valve, but it would idle very low for the first couple of minutes from a cold start.

I dunno what the stuff inside the red circle is. It might well be something to do with EGR or Pulsair cos there's some other hoses there in that picture that I don't think I've got on mine either.

Post by **RandomHero** » 21 Mar 2006 11:17 am

The red markings on the first picture have nothing to do with the AAV. I used that picture before to point something out. The thing i marked is the breather hose from the manifold to the air box.

Post by **sjs** » 01 Apr 2006 01:48 pm

The redmarked thing in the first picture is the Pulsair system on a B200E engine. Basically it's idea is to get a part of the exhaust gases to go into the intake manifold again, and thereby get cleaner emissions from the engine. So less pollution.

The auxilary air valve is the thing with the WHITE connector IN THE MIDDLE of the intake manfold. The AAV is bolted to the valve cover, and also sits by the second "V" in the "volvo" text, and has a cable coming UP from it.

Post by **RandomHero** » 03 Apr 2006 10:14 pm

That's what i said in this post

The red marks havn't got anything to do with the starting post. And it is not the Puls-air. The points are there to tell it's underneath the puls-air valves