My car, has idle problem, almost can't start up, if not by unplug purge valve hose, or step on gas paddle to maintain throttle body certain opening. Get a code P0172, rich condition. Another code P0106 I think came from my unplug purge valve hose. I ordered an idle control valve, not sure if this is the cause.

 

Year of car and engine type 4 cylinder or V6?

P0106 is the MAP sensor. An engine intake air leak can cause this code.

Check the valve by blowing air through it. Should be closed when not powered.

How does the engine run when driving? Has the MPG dropped?

 

4 cylinder, p0106 May be caused by I unplugged the purge valve hose connected to the throttle body. I can't understand why p0172 code come, and such bad idling. Engine shaking. Also 2 spark plugs wet. Could it be because of bad idle air control valve? Someone said because of intake manifold dirty. But how can it be bettered by let fresh air come in throw purge valve hose port?

 

Year of car and engine type 4 cylinder or V6?

How does the engine run when driving? Has the MPG dropped?

If fuel air ratio is high, adding air after the filter will lean it out.

 

1996, the can with dashpot and vacuum hose I changed is still used one. Running very rough like a wild horse at the beginning, now somewhat better. I guess MPG dropped.

 

Is P0172 code means too rich of mixture.

Check for air leaks between air cleaner box and MAP sensor.

Check for exhaust leaks.
High fuel pressure.
Leaking injector
Bad A/F sensor bank 1, sensor 1..
ECT
MAF. Can try to clean MAF. Read up on this on internet.

 

I changed MAP sensor, Oxygen sensor. Last night I check coolant temperature sensor, no problem. Maybe on Saturday I can check exhaust leak with my collage's tool. I can't find MAF, but intake air temperature (IAT) sensor.

 

See private message sent.

 

some spark plugs are wet, some boot for the spark plug is wet. Where is the problem? Code P0172

 

What part of the plug is wet, electrode or insulator?

What is the boot wet from? Gas, oil, coolant? A wet boot could cause grounding of the electrode and engine miss!