Almost stalling at idle, 2x random misfire codes + rich exhaust bank 1. Need direction.

Crunchbite

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2007 3.7 limited.
i’ve replaced all 4 O2S, and replaced the three driver side ignition coils. i’ve removed and cleaned all spark plugs, and gently cleaned the MAP sensor with appropriate spray. this problem is almost unnoticeable until about 70-80kmh, when my revs will die down to about 1400-1500. at a stop sign, or especially sitting in park for a few minutes, idle will drop to 400 and shake the car, and CEL lights up.

This is at its worst if i fill my gas tank from near empty to full. scary leaving the gas station, it will literally stall.

my ideas are bad cat, or something electrical. PO treated this car like crap. i also have the wierd extra fan attached to the water pump. i have an obd2 that reads live data, just don’t know what to look at.

please offer suggestions!
 

LibertyTC

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Can you read the stored code/s ? Post back any specific OBD2 code numbers.
The 2007 may have the new drive by wire technology, and codes could be related.
Do you have a fuel pressure gauge? If not get it to a shop, need to know the fuel pressure readings.
example: Key on reading. Leak down key off, letting it sit for 15 minutes reading.
 

Crunchbite

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Can you read the stored code/s ? Post back any specific OBD2 code numbers.
The 2007 may have the new drive by wire technology, and codes could be related.
Do you have a fuel pressure gauge? If not get it to a shop, need to know the fuel pressure readings.
example: Key on reading. Leak down key off, letting it sit for 15 minutes reading.
Thanks for the reply;
My scanner read two P0300 codes, and one P0172.

I do not have a fuel pressure gauge, but it’s in the shop on Monday so i will ask them to do that.
 

LibertyTC

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P0300 = Multiple Cylinder Misfires & P0172 = 1/1 Fuel System Rich
What spark plugs are installed? Use only NGK ZFR6F-11G .. set gap to.040 inch.
What brand of coil packs did you purchase? Its always best to install 6 new coil packs.
Mopar coil$ are best, however Standard brand worked well for me.
Consider the coil packs a tune up item.
 
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derekj

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Try isolating the purge valve from the intake manifold - could be sucking fuel in through the vapor line.
 

Ksat

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Try isolating the purge valve from the intake manifold - could be sucking fuel in through the vapor line.
Excellent advice.

What brand O2s did you use? NTK are the only ones you should use. Anything else could set you up to chase ghosts.

Rich conditions rarely cause misfires, so your 2 codes may be unrelated to each other. Does the CEL blink at all when driving?
 
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