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Discussion Starter #1
>Hello out there. I need to know how to adjust the fuel/air mixture on my 77 280z. My MPG is way down (like 16-18mpg), the plugs are fouling every 4 or 5 months and the exhaust reaks of unburned gas (which fills the inside of the car whenever the window is down). The Chilton's manual says it needs to be done using a CO meter, but I just want to thin out the fuel mix a little. Please help ASAP.

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If you have acess to a meter that's the only accurate way to do this (I just adjusted my fuel air mix on 76 280Z) but unfortunately I don't know of any other ways to tell where the proper mixture is
 

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> [email protected]
First check to see that your cold-start valve and thermo-time switch are working properly. These control the choke for fuel injected systems. If they stay on after the engine is warm your engine will be running too rich.

Next, check to see if you have a removable plug in your air flow meter. The plug covers an air bypass valve that will allow you to adjust the mixture ratio somewhat. Many replacements do not allow adjustment.

Any exhaust smell in your car with the windows rolled down indicates a bad rear hatch seal; it's allowing exhaust fume to seep back into the car (rolling down the windows create a vacuum inside the car which sucks in the fumes from the rear. The smell is more than annoying so be careful. If you are getting headaches you may be suffering carbon monoxide poisoning. You won't die but the headaches can be fierce.
 

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Discussion Starter #4
> First check to see that your cold-start
> valve and thermo-time switch are working
> properly. These control the
> choke for fuel injected systems.
> If they stay on after the engine is warm
> your engine will be running too rich.

> Next, check to see if you have a removable
> plug in your air flow meter. The plug covers
> an air bypass valve that will allow you to
> adjust the mixture ratio somewhat. Many
> replacements do not allow adjustment.

> Any exhaust smell in your car with the
> windows rolled down indicates a bad rear
> hatch seal; it's allowing exhaust fume to
> seep back into the car (rolling down the
> windows create a vacuum inside the car which
> sucks in the fumes from the rear. The smell
> is more than annoying so be careful. If you
> are getting headaches you may be suffering
> carbon monoxide poisoning. You won't die but
> the headaches can be fierce.

I'm having the same problem especially with the exhaust smell in my car. I have all new rubber being that I just restored the car. I even had my body man use this special machine that detects any leaks in the inside of the car. It showed that my hatch is totally sealed yet I still get a god awfull amunt of exhaust in the car (with windows open). Any other Ideas?
 

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Try this.

move the boot that covers the connection to the o2 sensor.

start the engine let it warm up then let it idle.

connect one lead of a digital meter to the connection and the other to ground.

adjust the screw on the airflow meter until the meter reads around 0.5 volts.

bring the rpms up around 2000 and keep it there. now look at the meter it should move around but it should be around 0.5 volts.

this should be a good start and should let it pass emmisions.

hope this help you out.
 

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> I'm having the same problem especially with
> the exhaust smell in my car. I have all new
> rubber being that I just restored the car. I
> even had my body man use this special
> machine that detects any leaks in the inside
> of the car. It showed that my hatch is
> totally sealed yet I still get a god awfull
> amunt of exhaust in the car (with windows
> open). Any other Ideas?

Check the seals around the shifting boot. It's a pretty common problem. When the windows are down, there is a vacume created, especially as your going down the road at high speeds. You can solve this problem, by

A) Leave windows up.
B) Use a new piece of rubber, around the hole that the center console sits on the tranny hump.

Let us know how it turns out.

Chris Behney
Redline Autosports
 

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Discussion Starter #7
> Check the seals around the shifting boot.
> It's a pretty common problem. When the
> windows are down, there is a vacume created,
> especially as your going down the road at
> high speeds. You can solve this problem, by

> A) Leave windows up.
> B) Use a new piece of rubber, around the
> hole that the center console sits on the
> tranny hump.

> Let us know how it turns out.

> Chris Behney
> Redline Autosports

Thanks Chris-However I checked this rubber and the inner shift boot rubber both are in good shape. I also sealed around the antennae drain,I even tried sealing the vents under the side insignias. I dont know what else could be leaking
 
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