P0171 and P0174

It was the MAF sensor thanks for the guides helped me fix it

Vehicle had a rough idle for some time. Then I had an overheating problem, the thermostat housing got damaged. Installed a new Housing with a new Thermostat then vehicle started working bad, rough idle and the Chek engine light came on. Had the MAF, Coolant Temp, TPS, Temp Sensors replaced and the Spark plugs and ignition Wires replaced. Worked a little better while it was cold but as it heated up it started working with a rough idle and sometimes cuts off. Whiel checking on it I noticed the Exhaust pipes were Flaming red hot. I removed the Catalytic converter and inspected it, the same thing happened So I replaced the Led wires and the converter stopped Flaming. But the check lights is still on and using a ODB2 I got a P0171 registered. Would the O2 sensor alone solve my problem? Thank you for any help.

I getting codes po171 & po174, I changed the fuel filter because the truck sits most of the time and reset the codes. This lasted about half a day, It was a daliy driver until a year ago.

When I bought it a egr code came up the first month, so I had a mechanic look at it he cleaned it and it was fine. But that was back in 2006.

I have the SOHC engine. I am getting the following seven codes: P0171, 0174, 0175, 0303, 0304, 0305 and 0306. Any help at all would be appreciated. Thank you in advance. I recently replaced all the spark plugs and was getting 171, 174 and 303. Now I have the above seven codes. Just trying to see where to begin in repairing this rough idle.

Additional: rough idle and fuel smell. Where do I start.

Issue resolved! Thank you turns out the number 3 plug was bad, intake hose you mentioned was split and also cleaned the throttle body and she accelerates quicker than ever.

I have a 2000 ford explorer 4.0 OHV. I had 2 codes come up for PO171 and PO174. When I looked them up on google it lead me to believe I needed a intake manifold upper and lower gaskets. After replacing them. I got one of the codes back PO171. Where do I go from here?

The cel has been on for 2yrs and my truck runs great it has had the same codes po171 po174 (lean condition banks 1 & 2 ). I need a smog this yr so I need the light off. I have to go to a star station per the state. I couldn't find any vac leaks etc, so I disconnected the bat so it would go out for the smog test. Well I passed all the tests except the function test b-cuz I erased all the monitors needed for that part of the smog test. So the tech told me it was prob the mass airflow sensor, so I spent 130, 00 on a new one while the light was still off I put it on and started a drv cycle to set the monitors so I could get a retest smog. So durning the drv cycle the cel came on same codes so I took the mas back and put the old one back on. I then paid the tech 65.00 to do a diagnostic check to find the prob he found a ever so slight leak in the intake manifold gasket area. So I paid a mechanic to change the gaskets and I barely got the truck home still running great just like always and the friggen light came on again. I'am at my wits end. I have been dealing w/ this since aug 2nd. I have read and watched countless videos I have searched countless sites for ans. All to no avail. However, I have learned alot about mechanics and my truck. But thats not getting the cel off. Do u think maybe the pcm is out of wack since the light has been on so long and the truck has ran great the whole time. I can't find anything wrong cuz there isn't anything wrong except the computer is wack. So can u p. Lease help me find the problem? Nobody else has been able to. I am out of ideas, out of $, out of time and out of my mind w/ this problem and I know more about mechanics then any female should (lol). Oh I almost forgot to mention it may not matter but, then it could be the key to the ans, ( what the hell do I know ) for the 2yrs that the cel was on it showed 2 codes 171 and 174 I know they r related to the lean condition banks 1 &2 but after the intake manifold gaskets got replaced and the light came back on it only showed the po171 code in the stored codes and under the pending codes it showed the 174 code but the total # of codes under diag was 1 code (po171) b-4 it showed 2 total and both were under stored and nothing under pending. So now im all screwed up. I don't know if that makes a bad situation worst or what. Please please please help me.

I believe he used carburetor cleaner and he appeared to be very skeptical about finding a leak, like he wasn't quite sure that there was really a leak but he couldn't find any place else that leaked. He even mentioned that he was wrong about it being the mas. The thing is that the gaskets were jacked, torn, glued etc, in the area he thought he detected the leak, yet the cel came back on. With a quickness too. Unlike b-4 it would take 2 drv cycles, this time not even 1. Do u think that part of the prob was corrected by replacing the gaskets, thats y only 1 code p0171 shows and not the po174?

Hi,

Engine miss during idle and acceleration. Codes p0171, 174 are coming.

Kindly let me know what could be the cause.

Thanks.