2G Engine error codes P0420 P1400?

[Spike3099]

P0420 Catalyst System Efficiency Below Threshold (Bank 1)

P1400 Manifold Differential Pressure Sensor Circuit Malfunction (Mitsubishi)

I know the p0420 is on because I do not have a cat. But I have heavy fuems on my eclipse and I am thinking it's because of p1400. What is that sensor?

 

[ADrewzki]

Originally posted by Spike3099
P0420 Catalyst System Efficiency Below Threshold (Bank 1)

P1400 Manifold Differential Pressure Sensor Circuit Malfunction (Mitsubishi)

I know the p0420 is on because I do not have a cat. But I have heavy fuems on my eclipse and I am thinking it's because of p1400. What is that sensor?

I think the PO420 is for your rear O2 sensor. You already know why that's going off. I'm not 100% sure but I think P1400 is your EGR valve. It's a valve that opens to let your rich exhaust get cycled back through the engine for a more complete burn. Your gas mileage is probably slightly lower because you're burning rich. Again, not positive but I had that code recently on my 95 Talon and I'm hoping I remember right. It's about $80 I think at my local auto parts store.

 

[98spydert]

Is it worth replacing the EGR valve or will a simple cleaning do the trick?

 

[crazyboy81]

I just got a P0420 as well but I have my cat. So does that mean it's bad or the rear sensor is bad?