# B11 vacuum part ID HELP PLZ



## TiredTrucker (Sep 11, 2015)

I bought this clean wagon, strong runner but missing that part. I've searched vacuum diagrams snd googled every listed part on vacuum diagram. I for the life of me not figure out what im missing. 
Car refuses to idle and is running so rich 10-15 mpg O_O


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## TiredTrucker (Sep 11, 2015)

Anyone? 
I'm seriously needing some help here....


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## smj999smj (Jan 1, 2006)

The picture's not the best, but that looks like the filter used in the VCM system, which controls the cold start fast idle. If it is, there will be a small hole on the end of the canister which should be situated on the bottom side when installed. If you hold your finger over the hole, the idle RPM should increase. It shouldn't cause poor gas mileage. Usually poor gas mileage on these engines is due to an improperly adjusted idle mixture. The idle mixture screw is located on the firewall side of the carb and comes with an aluminum plug over it from the factory, which won't be there if it was ever adjusted. You need an exhaust gas analyzer to properly adjusted the mixture and the procedure is listed in the factory service manual. It's been a long, long time since I had to adjust one, but I think you had to get the engine warmed up to normal operating temperature (make sure your thermostat is working properly) and then install the exhaust probe of the emission analyzer into the tailpipe. I believe the fuel enrichment solenoid was unplugged and the idle mixture screw adjusted to whatever the service manual calls for (I remember it being on the rich side); when you plugged the fuel enrichment solenoid back in, the mixture would lean out to an appropriate level to pass inspection standards (of the day). If you could adjust it in spec, you often needed to rebuild the carb. This is all assuming that the engine was good mechanically. Also, make sure the head temp sensor (aka "engine coolant temp sensor") is working properly and make sure the PCV hose isn't collapsed.


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## TiredTrucker (Sep 11, 2015)

Thanks 999
*allegedly* P.O. had carb rebuilt. 
So I'll have to screw with air fuel....
I capped the two vacuum lines for my missing mystery vacuum whatchamacallit LoL.

I only have $450 in this car but was hoping to sell it for a bit of profit to fund my 86 300zx project


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