On 1985 models (12a), the air/fuel mixture can readily be checked with a tachometer. An incorrect reading can indicate either improper mixture adjustment or a bad oxygen sensor. However on this model, one must disconnect the check connector for the air/fuel solenoid; and, here in is my question. Where is the location of the air/fuel solenoid?

Once this is located, I will attach a dwell meter (red lead to the air/fuel solenoid connector and black to the engine). The reading should be 20-70 degrees.

The air/fuel mixture is not set properly because of the residue that I observed when I changed my spark plugs. In addition, the car is misfiring because the residue is not allowing the trailing plug to fire correctly.

Any help locating the air/fuel solenoid would be appreciated.

 

You can't check your air/fuel mixture with a tachometer. You set your idle with the tach. You need an exhaust gas analyzer to set your mixture at .10% CO. THe best you can do is use an O2 sensor to get as close to stoich as possible. You also need to remove your gas cap when adjusting idle in addition to the solenoid.

 

Oh, the solenoid is on the passenger side of the carb, upper most solenoid in center.

 

Tubbymother what type of residue are you talking about? Just by knowing what it is, you know if it's running rich or lean...make sure your carb is adjusted properly and clean, check float bowl level, make sure timing is correct and that your engine's rotor oil seals are ok, before you attempt to adjust the mixture screw...

also incorrect sparkplugs will get fouled easily...

 

The air/fuel mixture can be set with a dwell angle set on four cylingers. On my tach I have a dwell angle function. Moreover, you are right about removing the gas cap.