I've got a 05 FFV taurus 3.0 . It is giving me these lean codes and starting to develop driveability problems. Worst time is morning cold starts. It will start hard, maybe 2-3 tries, then might die a couple of times getting out of driveway.. It is running on E85. It's symptoms are similar to the earlier problem it had before Ford Engineering could program the pcm correctly. Only no codes at that time. Since they recalibrated it, it has been fine till now. After the car gets going, It seems fine except I think the gas mileage is down. Checking for sure on this fill-up.

I have replaced the air and fuel filters. Cleaned the MAF sensor. Fuel pressure seems to be fine. Had 80# when dead heading the pump. Scan tool read in low 40's while running. I haven't been able to do a running test with my gauges yet because of a clearance issue with an engine mount. I have also checked for vacuum leaks with a can of carb cleaner and can find nothing. Any help would be greatly appreciated. THANKS

 

I have read some of these other post with people having cam pos sensor and synchro problems. I do get a squeaky noise especially in below freezing temps. I had been blaming that on the altenator. Do not have the 340 or 1309 codes however. Any Possibilities?????

 

I don't know if I stumped everyone or if it is because this section isn't seeing alot of traffic but I thought I would post an update. I switched it back to regular gas and it ran fine. Went back to E-85 after one tank of gas and it still starts and runs fine. ??????????

 

i would say vacume leak, this is a common thing in the 5.4 forum, double check for vacume leaks.