[Doug]

Replaced the PCV. Turns out on the 2.3 duratec, the hose that connects the PCV to the intake manifold is prone to collapsing and cracking. I found 2 huge cracks in mine. 24.5 MPG on my last trip.. better than EPA! Hope this helps someone.

[Doug]

I picked up a wifi OBD2 scanner and am using an applicaiton called FORSCAN to pull PCM data.

Graphed in the attached pic are

coolant temp
short term fuel trim
long term fuel trim
MAF
upstream sensor voltage
downstream sensor voltage

When idling, the upstream O2 sensor is oscillating every ~2 seconds. At 2200 RPM, the oscillation is very close to one second.

The downstream looks like it’s bouncing quite a bit. Could this be a sign of a bad cat? or could the upstream just be bad?

Attachments:

• 1.jpg

[Doug]

Thanks all. I’m the only one driving, and I’m 99% sure gas isn’t being siphoned.

I am calculating based actual miles between fill ups. I guess I will start by looking at the O2 sensors (they aren’t very expensive).

Am I correct in assuming the upstream would affect MPG?

[Doug]

Thanks Eric. This is not a flex fuel vehicle.

I looked at the Poor MPG link, and I see few things that I haven’t looked at yet.

Are there any particular items below that could cause a sudden loss of ~30% MPG, with little/no loss of power?

O2 sensors
PCV Valve
EGR Valve
Vacuum Leaks
Exhaust Restrictions/Leaks
Fuel System issues
Evap System
Mechanical (hope not!)

[Doug]

Thanks for the replies so far. I took the vehicle for a drive today. Checked all 4 wheels and didn’t notice any hot drums/calipers. I even jacked them up and they spin freely.

I did take it by Advance. Granted they don’t have an advanced scanner–but it didn’t pull any codes.

If the Escape does has any loss of power in the low end, it is minimal at best. This 4-cylinder never had any pep to begin with!

[Author]

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