I Gots Codez!

[Mean98GT]

Yay I pulled more codes from the check engine light tonight!
P0118 - Engine coolant temp high circuit output
P0401 - Insufficient EGR Flow

What is going on!?
Any help greatly appreciated.

 

[Pennywise2]

P0118
A bad connection at the sensor.
An open in the ground circuit between the sensor and the PCM.
A short in the voltage feed between the sensor and the PCM.
A bad PCM.(less likely)
A bad temperature sensor. (shorted internally)

P0401
The EGR valve is faulty and needs replacing.
There is a blockage in the EGR tube,most likely carbon build up.
The EGR valve may not be opening due to a lack of vaccum.

What are your current symptoms?

 

[Mean98GT]

running sluggish. misfires at WOT (but i have a bad o2 sensor, and i just need to get the new one in). Other than that nothing really. fuel economy hasnt changed much. I went through my engine bay last night and found three plugs that arent plugged into anything!!! The egr could be from one of those plugs????
On the p0118 what do you think would be the most likely problem? I want to start somewhere and go from there. Ive tried the guess and check with a lean code in the past and that was a pain.
I feel like the sensor is crap. My old one corroded and just broke in half and I picked up a new one from advanced auto and maybe they gave me the wrong sensor, maybe they gave me the one that connects to the stock gauge instead of ECT sensor??

 

[Mean98GT]

question: Is the sensor for the ECT (one that reads to the computer) and the sensor which feeds the gauge... Are those two different sensors, or are they the same? If they are different then the advanced screwed up and gave me the wrong one. But I picked up another sensor from autozone which appears different.

 

[Pennywise2]

P0401-Probably a bad EGR valve that needs to be replaced.

P0118-Could possibly be a number of different things.
The coolant temperature sensors are probably faulty I'd replace them both though just to be safe.
Driver side=Is for the temperature gauge in the instrument cluster.
Passenger side=is for the PCM.
Your thermostat could be stuck open and be faulty.
Your coolant level could be very low.
I subjest you completely flush and refill your coolant anyway since you will be in there.

 

[Mean98GT]

oddly enough my pcm is on the driver side. stock gauge cluster is on the passenger side.

 

[walkingdisaster]

Reviving an old thread because I didn't want to make a new one.
I have the p0401 code and I tested the DFPE sensor and got 5 volts on one wire and about .3 volts on another.
This means the switch is okay right?
Where should I go to now for diagnosing it?