[Yvette]

I took my 77 in for emmissions and the mechanic told me that it was running too rich and didn't even know where to start looking for the problem. I told him not to touch it till I could get into this forum and ask what you guys thought (aside from finding another mechanic!). He says it's running at 10% and should be below 3%. Any ideas?
Thanks
Yvette

 

[johnb510]

Clean all the FI connectors (including the ECU connector)! That is a good place to start. Pay close attention to the water temp sensor and the bullet connectors which are located about 1 foot back in the harness from the water temp sensor and thermotime sensor. The water temp sensor (and thermotime) are located on the thermostat housing. The water temp is below and to the right of the thermo transmitter (to temp gauge in the dash, will have a single bullet connector) and the Thermotime is to the left and slightly below the water temp sensor.
Will be sort of like this (looking from the front)

dash
thermo trans.

water temp
sensor

thermotime
sensor

The water temp sensor and thermotime will both have FI style connectors.
There is a ton of info on passing emmisions in the archives...do a search.

 

[Zuber]

Also, make sure your idle is set correctly. Should be 800 for your year (unless it's an automatic).

One other thing if you don't find corroded connectors like all the rest of us play with. There is an adjustment on the outside of the AFM that controls idle enrichment. If your plugs are in good shape, you have no vacuum leaks, and all your sensors and connectors are working right, you might try having the AFM adjusted. Someone could have monkeyed with it. Normally I would say leave it alone, but if all else fails...

Screwing the screw in will make for a richer mix. Screwing it out will lean it out. Unless you have the right equipment, you won't know if you are making any worthwhile changes.

One other thing. Check that your TPS is working correctly. At idle, the idle contacts should be making. As soon as the throttle moves off idle, they should break, and no other contacts should be making. At 35% or so of throttle movement, the WOT contacts should be making. These two contacts allow for smoother running at idle, and more fuel at wide open throttle (keeping it from leaning out). If misadjusted, you can have problems. Clean the contacts, and if needed adjust. If you adjust and the car starts running different, be sure to readjust your idle to the proper rpm.

Basically though, a clean air filter, fresh oil, new plugs, and a good PCV valve should see you through the emmisions tests.