Auxiliary air valve - D-jet

DJSimca

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or Zusatzluftschieber ;-)

Mine is acting up, i.e. first it didn't open enough when the engine was cold, now - after removing it in an attempt to give it a bit of 'work out' - it won't close properly !!!
As far as I understand this valve is supposed to be fully closed at around 70 degrees C.

This means that I cannot adjust idle down below 1500 rpm - even with the idle switch completely closed!! If I block the auxiliary air hole (right next to the cold start valve) the engine runs fine (engine warm) and I can adjust the idle via the idle screw.

I can get a new AAV from Bosch but firstly is it very costly and secondly I don't know if this is old new stock, i.e. a 30 year old part or newly made.

Has anyone found a more 'contemporary' solution/workaround for the 'good olde AAV?? Could an AAV from another car be made to fit/work?
 

pamp

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Aux. air valve

I retrofitted a valve I had in my parts stash...again I hope not to upset people...Volvo. From a 1971 B20 e motor. Bound to find a good one at the bone yard...yet I am sure I did not have to do this.
What I eventually found, and I am being redundant as per my previous posts, the coolant block where the aux. air valve and coolant temp sensor are mounted was choked with crap. I found this using an I.R. thermometer and measuring temp in and out as the engine warmed up. Pulled and cleaned the block and problems solved. My symptoms were a way over rich condition. I would recommend to anyone using d-jet to check this part. Bitch to pull for sure, but if your coolant is not flowing free through here, mayhem results. BTW the prices for the infra-red thermometer have come way down and a for sure handy tool for the shop.
 
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Stefan

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or Zusatzluftschieber ;-)

Mine is acting up, i.e. first it didn't open enough when the engine was cold, now - after removing it in an attempt to give it a bit of 'work out' - it won't close properly !!!
As far as I understand this valve is supposed to be fully closed at around 70 degrees C.

This means that I cannot adjust idle down below 1500 rpm - even with the idle switch completely closed!! If I block the auxiliary air hole (right next to the cold start valve) the engine runs fine (engine warm) and I can adjust the idle via the idle screw.

I can get a new AAV from Bosch but firstly is it very costly and secondly I don't know if this is old new stock, i.e. a 30 year old part or newly made.

Has anyone found a more 'contemporary' solution/workaround for the 'good olde AAV?? Could an AAV from another car be made to fit/work?

Hej!

I simply bought a used one.

I also did try with some "work out" on the old valve, but totally hopeless.

If you are going to buy a used one, be sure the one is tested in a pan/boiler together with a thermometer to verify the closing/opening temp and stroke. The guy I bought from did that and posted the photos from the test before the deal!!

There is always a chance that a used one will end up working tomorrow, but who knows? :)

//Stefan
 

damienh

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I got an excellent deal on a brand new one from an ebay shop in the US (I'm in the UK). Works perfectly fine. If you're still in need let me know and I can pass the details to to you and perhaps they have more.
 

koldo1

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i have also problems with AAV

hi all:
I have problems with the AAV in my CSI of 1973. The valve never close the pipe totally. Ass I know it must close when the engine is hot.
I want desasembly from the middle and clean it inside. Is it posible?
thank you
 

Stefan

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hi all:
I have problems with the AAV in my CSI of 1973. The valve never close the pipe totally. Ass I know it must close when the engine is hot.
I want desasembly from the middle and clean it inside. Is it posible?
thank you

I would say no!

First:
Since all moving parts is sealed inside the casted aluminum it is almost impossible to clean the parts.

Second:
The valve is probably not stuck due to dirt.
More likely is the heat expanding material that is obsolete and does not give full stroke of the cylinder to close the air inlet (common for this part).
 

koldo1

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I would say no!

First:
Since all moving parts is sealed inside the casted aluminum it is almost impossible to clean the parts.

Second:
The valve is probably not stuck due to dirt.
More likely is the heat expanding material that is obsolete and does not give full stroke of the cylinder to close the air inlet (common for this part).
hi,
I need to buy it new :cry:. Maybe I can find something second hand...
thank you.
 

koldo1

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cal csl

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I had exactly the same problem and bought a new one from W+N and still had the same problem. Found that completely flushing cooling the system, cleaning out the fitting/ block the temp gauge then going on a hard drive fixed it for a bit. Had a feeling maybe the rusty heater core might of been the problem as there was still a fair bit of rust in the system. Now fully rebuilding car so hopefully wont have the same problem again when it is up and running
 

sfdon

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at the boneyard today in Newark. $4 bucks.
 

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