Code P0171 problems
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CODE P0171
Ford F-150 2001 Pick-up 148 miles
i have already replaced tthe MAF sensor,cleqned the throttle body just put in a PCVassembly and replaced all 4 02 sensors yet its still throwing P0171
1 reply
BA
i showing a P0171 ON Y BANK 1 AND A 174 ON MY BANK TOO HELP IVE CHECKED EVERY THING FOR LEAKS WHAT NOW IT STALLS WHEN I AT THE LIGHT
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CommentWhen I smoke the motor smoke comes out of my Egr and iac 
Solved
Ford F-150 1999 5.4. 4x4 232000 miles
Smoke comes from the Egr not gasket issue it's coming from under the top part where vacuum hooks up to also smoke comes from iac looks like it's coming from the little round part on side and also from unit itself.do these parts suck outside air or are they leaking. Also truck has code p0171 lean on bank 1 that I can't figure out. Any help would be appreciated. I also started the truck and tried the o propane gas bottle and carb cleaner and sprayed it around both WITH no change in motor running. Not sure what to do next except change plugs injectors and coil packs and see if that will solve my p0171 code.
3 reports
Best answer (according to Joey)
I just had this problem as well. I took truck into garage and had intake gaskets replace new hoses and new intake. This cured my issue. Certainly something you may want to have looked into. Job was a little expensive but it was well worth it and I got a great deal on it. They found my intake was cracked, the tube behind intake had somehow broke and was leaking coolant, My truck shook at idle and take up with little power. This job can cost at much as $2000 but it was 1/2 cost at my local garage. I just got truck back and Its like its brand new. Good luck
Thank you I smoked the motor again and now have no visible leaks anywhere and we smoked it good so now I'm thinking I've got bad sensors.
Comment1 report
P0401 is the egr system, insufficient exhaust gas flow. 171 ad 174 are both lean condition codes, engine is getting too much air or not enough gas
My code reader tells me that, what i need to know is how to fix the problem. I have cleaned and checked the EGR valve it holds good vacuum. I cleaned the throttle body and ports, replaced the gas cap twice, and it continues to kick the codes.
Have you checked for vacuum leaks? pcv,hose from pvc to the back of throttle body? Maf sensor
Yes and yes, have not checked thev mass air flow sensor, will check next Thanks
CommentMajor loss of power
Ford F-150 1999 5.4 350000 miles
Im getting a P0161 code P1151 p1131 P0156 P0136 P0171 P0184 N0406 codes 1999 ford F150 5.4L I've changed maf sensors ege sensor's and throttle position sensor also blinkers and power mirrors stopped working I've checked for vacuum leaks also it's got me stumped
1 reply
Check cvt or vvt solenoids there are 2 and they can cause all sorts of havoc just before they fail completely. Then it will feel like timing chain snapped. Use only genuine ford replacement though. Found out hard way using cheap dorman type.
Comment5 reports
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