running rich 2200
fishmonster13
03-18-2005, 06:44 PM
my truck is running extremely rich , i have rebuilt the carb installed a new feul mix solenoid ,installed a new o2 sensor changed out the distributer ,plugs, wires ,cap rotor ,checked and double check the timing , good compression , good valves jsut did valves seals a couple of months before it started runnign rich. can anybody help me with this
onelow_mazda
03-18-2005, 07:47 PM
Double check your vacuum lines. Sometimes they can cause major headaches if not connected exactly where they came off. As I learned the hard way.
89B2200
03-18-2005, 08:22 PM
If your vacuum lines are leaking, you will run lean because of extra unmetered air coming into the intake. It is not vacuum leaks.
How did you know you are running rich? Is it smoking black?
Is it running rich at idle, part throttle or WOT?
When you rebuilt your carb, did you check the float level?
Only way to check A/F mixture is to backprobe the O2 sensor at idle, part throttle and WOT when engine is at operating temp.
O2 sensor output at perfect A/F ratio is 0.5volts and varying to +/- 0.3 volts and always crossing 0.5 volts.
Lean is <0.5 volts and rich is >0.5 volts all the time.
The computer controls the mixture solenoid so the O2 sensor output crosses 0.5volts as many times as possible.
Backprobe the O2 sensor and tell us what iyou found out.
How did you know you are running rich? Is it smoking black?
Is it running rich at idle, part throttle or WOT?
When you rebuilt your carb, did you check the float level?
Only way to check A/F mixture is to backprobe the O2 sensor at idle, part throttle and WOT when engine is at operating temp.
O2 sensor output at perfect A/F ratio is 0.5volts and varying to +/- 0.3 volts and always crossing 0.5 volts.
Lean is <0.5 volts and rich is >0.5 volts all the time.
The computer controls the mixture solenoid so the O2 sensor output crosses 0.5volts as many times as possible.
Backprobe the O2 sensor and tell us what iyou found out.
fishmonster13
03-18-2005, 08:34 PM
i back probed the o2 sensor it stays around .6 and it doesn't fluctuate at all . it smokes really bad the plugs are black with running the truck for a minute
89B2200
03-19-2005, 05:18 AM
Good info. You are definitely running rich.
Did you check with a fully warmed up engine? It's important.
If it's rich at idle, the idle mixture screw could have been tampered or misadjusted. I adjust the idle mixture screw while backprobing the O2 sensor. Set it at <0.5 volts.
If it's rich at part and wot, the a/f mixture solenoid or the computer is shot. You can test the a/f mixture solenoid by resistance test. It is either open or shorted.
If it turns out good, then your problem is the computer.
I have a spare computer for an 89B22 that I can loan you. Just pay the shipping and if it fixes your problem, you can either return it or buy it for cheap.
Let me know.
Did you check with a fully warmed up engine? It's important.
If it's rich at idle, the idle mixture screw could have been tampered or misadjusted. I adjust the idle mixture screw while backprobing the O2 sensor. Set it at <0.5 volts.
If it's rich at part and wot, the a/f mixture solenoid or the computer is shot. You can test the a/f mixture solenoid by resistance test. It is either open or shorted.
If it turns out good, then your problem is the computer.
I have a spare computer for an 89B22 that I can loan you. Just pay the shipping and if it fixes your problem, you can either return it or buy it for cheap.
Let me know.
89B2200
03-19-2005, 05:20 AM
I saw tht you rebuilt the carb and put a new a/f mixture solenoid.
Then it could be the computer.
Then it could be the computer.
fishmonster13
03-20-2005, 06:18 PM
any one have a computer for sale cheap
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