Two ECM trouble codes P0153 and P0174

KNIGHTSCHARIOTS

MEMBER
2001 FORD ESCAPE
3.0L
V6
4WD
AUTOMATIC
301,000 MILES

I have scanner freeze frame data for the code P0153. As follows (Calc load 43.1 -% coolant temp 198 degrees. STFT1 negative 0.8% LTFT1 5.5 % STFT2 9.4 LTFT2 9.4 engine RPM 1923 vehicle speed 42.0.) . These issues and the mil light illuminating appeared after a fuel up. And the vehicle mil light went out after changing the DPFE sensor and has illuminated on and off since first occurring. I suspect maybe EGR or IAC or evap purge valve or canister contamination as possible causes. Haven't had time to recheck for a vacuum leaks. The engine runs fine at mid to wide open throttle but when parked or in drive the idle changes from a normal idle to an erratic idle. When in park from time to time it will almost stall then recover to a normal idle. MAF sensor has been about 3.86 to 3.89 with a snap throttle. Fuel pressure is within normal ranges at KOEO and KOER. So I don't think its a fuel supply issue. I'm leaning more towards vacuum leak or a sensor malfunctioning. Thanks for your help in advance.

3 Replies

BMDOUBLE

MECHANIC
1,139 POSTS

What we need to do is pull up your data stream and select o2s11 and o2s21 sensors, then get a can of brake clean or throttle body cleaner and spray the base of the intake manifold then look at the data stream of the sensors. They will peg to 1.0 volt with the presence of a vacuum leak while you sprayed the chemical at the intake. More than likely you will need to replace the upper intake gaskets/o-rings, and the spacer gaskets/o-rings as well. I've done tons and tons of them! Your freeze frame data will probably show a low coolant temperature when the codes were set because the gaskets leak worse when you first start the vehicle.

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