I've put down a good 3,000 miles on my 2008 V10 6.8L since May and it's been running like a top without issues until yesterday when I was driving out to middle of now-where Idaho. I made it 100 miles out of Boise on a mostly uphill trip doing 45 - 65 mph, when I noticed the van was really struggling to accelerate on the uphills and not able to go faster than 40mph - my GF was driving at the time and when I hopped behind the drivers seat I immediately noticed something was wrong.
Main symptoms were:
- loss of power - very little throttle response, flooring it and not getting any increase in RPM or speed. Not able to get above 45mph.
- sputtering / fluctuating RPM around 500RPM at idle, typical idle is closer to 1000RPM
- Then came the check engine light with a code P0191 and a P0301 misfire on cylinder 1. Code P0191 is fuel rail pressure sensor circuit problem ( I keep an OBD II reader in the van)
All fluid levels were normal: oil, radiator, tranny were good.
At this point I was well out of cell service and 20 miles from the nearest gas station. Tried to get a AAA tow to no avail (by hitch hiking back and forth to said gas station) and camped out last night on the side of HWY 21.
I have the haynes manual for the E350 van and based on the code decided to relieve the fuel pressure, uninstall, and reinstall the fuel rail pressure sensor and see what would happen. The wire harness and connector pins looked fine, sensor visually looked OK, there was a little bit of dirt build up on the mating surface of the sensor and the fuel rail which I cleaned up before reinstalling.
Engine started right up and felt completely normal, getting up to 75mph without issue and given the location I decided to bail on my planned 4 day camping trip and return to Boise. 100 mile drive back was non-issue, I don't get what went wrong but plan on replacing the sensor and fuel filter anyway just for good measure.
Has anyone experienced anything similar? Any thoughts or trouble shooting tips? Really perplexing behavior. The only thing different about this trip compared to any other in the last 3 months was that my girl friend was driving ... LOL so obviously it's her fault