If wishes were wings, frogs wouldn't bump their butts, either.

 

Okay, similar issue, my 2004 F-150 Heritage 4.2 with 116K miles has a condition that causes the engine to run rough during the warm up cycle. The local auto parts store code reader would say the old P0171 / P0174 codes, they would clear and run fine. The only time this occurs is right about the time the engine goes closed loop during the warm up cycle. I have done the plugs, the PCV hose and checked all over for vacuum leaks and found none. I just got a proscan diagnostic tool and it only shows the P2195 / P2197 codes. However, once the engine is up to operating temp everything is running fine, no codes, O2 Sensors cycling, etc. The question I have is the isolator bolts / gaskets that apparently all 4.2 V6 needs, would this cause this issue where the engine is still warming up but goes away at Operating temp, (parts expansion at different rates).

 

Well, for cold idle concern, -check IAC.

CHECK THE VPWR VOLTAGE TO THE IAC VALVE

IAC Actuator connector disconnected.
Key in ON position.
Measure the voltage between:

( + ) IAC Actuator Connector, Harness Side ----( - ) Vehicle Battery
-------------VPWR - Pin 1 ----------------------- Negative terminal

Is the voltage greater than 10.5 V?

No= REPAIR the open circuit.

_______________________________________________

CHECK THE RESISTANCE OF IAC VALVE

IAC Actuator connector disconnected.

Measure the resistance between:

( + ) IAC Actuator Connector, Component Side
IAC - Pin 2

( - ) IAC Actuator Connector, Component Side
VPWR - Pin 1

Is the resistance between 6 ohms - 15 ohms?

No = INSTALL a new IAC Valve.

__________________________________________________ ______

CHECK THE IAC VALVE FOR AN INTERNAL SHORT TO THE IAC CASE


Measure the resistance between:

( + ) IAC Actuator Connector, Component Side.
IAC - Pin 2

( - ) IAC Actuator Connector, Component Side.
IAC Case

Is the resistance greater than 10K ohms?

No = INSTALL a new IAC actuator.

______________________________________________

CHECK THE AIR INLET FOR PLUGGING OR A STUCK IAC PINTLE

INSPECT the entire intake air system for debris, blockage or other damage.

Remove and inspect the IAC valve and check the pintle movement. Check the air tubes (if equipped) for blockage or damage.

Remove and inspect the air cleaner element for excessive dirt.

Is the IAC valve and intake air system OK?

No = INSTALL a new IAC valve, or REPAIR the air inlet as necessary.

 

Okay, will do those tests tomorrow but one thing else I forgot to mention, When the engine first started it runs fine, it doesn't start to act up for about 5 minutes then the engine starts to stumble and the P2195/P2197 came up as a pending code, the CEL never came on this time. It also has a CAI with K&N filter on it. All connections are tight and the MAF has been cleaned with CRC MAF cleaner.

 

Very likely. Mine first showed up in freezing weather then went away. While I was experimenting with all the other less expensive causes, and thought I'd fixed it, it would always come back around the time you said. Finally did the bolts and gaskets (about 30K ago) and the codes never returned.

Check all the cheap stuff first, a simple vac leak or exhaust leak can cough up those codes too.

Good Luck
Jim

 

...

 

Okay took some data today, monitored engine temp, MAF flow, O2 Bank 1 Short Trim and O2 Bank 2 Short Trim during cold start to normal operating temp. Initially the O2 Trim was + 34 % on both banks and steady as was the MAF flow. At approx 90 deg the O2 Short Trim dropped to 0 then back to + 34 % over a 20 sec period. IT stayed there until the engine temp hit 130 deg then the O2 short Trim dropped back to 0 and stayed there. The engine began to run rough and the MAF flow began to oscillate. Continued to monitor until reaching normal operating temp and the O2 trim never chsanged off 0. I stopped the trend and checked for codes and the P2195 & P2197 was showing as a pending code, the CEL never came on and never got any hard codes locked in. I cleared the two codes, the engine began to idle correctly and the O2 Short Trim returned to controlling in the + 27 range and then slowly reduced to the +13 to +18 range on both banks. I double checked for vacuum leaks again and found none. I plan on checking the IAC tomorrow, the front O2 sensors (Bosch) are both new and less than 5000 miles. This condition was coming in prior to the O2 sensors being changed. I'll continue to check to cheap stuff before I dive into the intake but it is looking more and more like that is the potential problem. Thanks for all the feedback.

 

...

 

Okay, have checked the IAC for issues and there are none. Also removed it and checked for debris in the manifold and if the pintal movement. The pintal was free and there was absolutely no debris in the manifold. I ran the proscan again but this time I immediately started driving and never got a code or saw a problem with the operation of the system. the only thing I can figure is the rapid warm up or the higher engine operating speed (not idling) masks the problem which makes a little sense because the only time this has occured is when I crank the vehicle up and warm it or when I am just puttering around. My normal run is to work and I am a block from 55 mph roads. So without and other reason I am planning on ther isolator bolts and manifold gasket replace, ahh such fun!!!!

 

Well an update with a happy ending. Finally broke off and got the isolator bolts and air box gaskets. Did the replacement last Saturday and running great now. Checked the O2 sensors with the laptop and they are both running right together now. Before they always read a lot different on the Bank 2 side. No check engine light and no other codes. Runs really smooth now. Was going to check the gas mileage but since old man winter just took a dump on northern Missouri and since I have to works nights for the next 7 days any mileage checks have gone out the window since I am now in 4x4. I will say this, the back 3 bolts on the air box were not fun to get to much less torque to 85 in/lbs!!! All in all took about 3 hours for the job. The iniside of the air box was actually pretty clean, minimal cleaning required. I also noticed a couple of the lower air box gaskets looked to have been leaking, gasket discolored.

 

Had the P2195 code on my 2010 Fusion SE 2.5L. What I found was the intake tube between the air filter and throttle body was lose and had popped off. The car wouldn't want to idle or run. Put the tube back on, and made sure the clamps were tight. Runs perfect and no code. Just a heads up for something else to look for.