plymouth383
New member
so here is the situation. I own a 2011 Ford Flex Ecoboost. It has 130k miles on it. It has been great up to this point. I have had hardly any problems with it. I am a mechanic by trade and do all my own work on vehicles. this one has me puzzled though.
It is tuned from Torrie at Unleashed.
It has a 3 bar Map Sensor
180 degree thermostat
About 6 months ago it began to misfire. I have experienced the misfires before and usually it indicates plug time on these. also a few days later it started this fun little lunging thing where the rpms rise up and down while going down the road.
1. I ordered up a set of the sp534s and installed them at .030. thought all was well until a couple days later it started to misfire again. figured maybe it was a bad plug I got. so bought another set reinstalled still no help.
2. figuring the mileage was high i did some research and came to the conclusion that possibly my intake valves are all coked up and needed to be cleaned. I pulled the intake apart and shot some walnut shells at the valves. The only ones that were truly really bad were the front two cylinders where the air tends to not hit directly. Got them all nice and clean.
3. I installed a brand new set of OEM injectors. I replaced all six. Figured while i have everything apart. old injectors looked good nothing to indicate a problem.
After reassembling everything I took it out for a test drive. Still misfiring. also still lunging. Now I was getting confused.
I have done a couple of datalogs after this to try and confirm if anything else was reading off and causing the misfire. Everything reads normal. The car misfires under high load lower rpm sessions. Say accelerating from a yield sign at about 15mph up to 40 with about 25 percent throttle. It will just continuously misfire until you tip into it and get it to downshift and accelerate. The only thing that is evidenced in the logs is the RPM change from the misfire. It runs very strong otherwise with plenty of power. it only does this is this range nowhere else. Also around the 25-45mph if you hold the throttle steady the RPMs will fluctuate up and down about 150-200 RPM. It does this constantly. The Throttle angle actual reflects this on the log as well. You can see it rise up and down with no change from the pedal, only the change from the PCM commanded throttle. It will move as much as 2 degrees on perfectly flat unchanged road. Even with the cruise control on it will not stop the lunging. I do not see anything else moving with this except for boost going up and down maybe. I am using the SCT software to datalog and I have to say the program is a little buggy. but the data doesnt seem compromised just hard to view.
So after doing some more reading and research I figured out that the TIP has a big play in the way that everything works. I know these are Speed Density so there is no MAF or anything like that to skew readings.
4. I loaded up the Stock Tune and then reinstalled the 2 bar map sensor. Went for a test drive and everything seemed ok. then a day later it came back. same things. Misfire and lunging.
5. I took the 3 bar map sensor I had for the tune and placed it in the TIP position. Same part number and everything. No change still misfiring and lunging.
really confused now I am just grabbing at strings.
6. I installed a brand new throttle body with new TPS and Motor. No change still lunging and misfiring
7. I installed 2 fresh wideband OEM Bosch O2 sensors. Runs smoother up top now but still no stopping of the misfire or lunging.
8. I verified and double checked the knock sensor wires even though there is no evidence in the log of them being an issue and the loom is in great shape. no chafing at all.
9. I installed 6 new OEM coils and 6 new spark plugs gapped at .30 then .28. Still misfiring and lunging.
I am just really frustrated at this point as usually I am not this clumsy or lost on a problem like this. I have tried to figure out how the system works and cannot think of anything else causing this issue. There has been NOT ONE check engine light or code set. The PCM thinks everything is peachy. Usually I diagnose and work it out step by step to reasonably determine the underlying cause but I finally am at a loss on this one.
The only variable that has been truly determined is that if you disconnect the battery or do a KAM reset that the problems soften and the progressively get worse. The misfire happens at any time. The fluctuating lunging rpm thing happens worse when it is cold and then gets better as it warms up. like 300 rpm in the morning but then when near work maybe 150rpm. you can almost always get it to misfire in the same speed rpm load range as stated above. Short of replacing the PCM i think I have covered everything that could be related to these instances.
This morning on a whim I disconnected the TIP sensor. It stopped doing the lunging but I could not determine the misfire bit really because of the Limp Mode and wrench light. Plugged it all back in and just went to lunch this afternoon and misfired right out of work and was lunging. It is really annoying to drive at times now. if you punch it while it does this is downshifts and takes off like a bat out of hell. it is powerful and doesn't feel mechanically weak.
PLEASE HELP! I am out of ideas for now. I can post some logs if requested tonight when I get home. Thanks for any help.
It is tuned from Torrie at Unleashed.
It has a 3 bar Map Sensor
180 degree thermostat
About 6 months ago it began to misfire. I have experienced the misfires before and usually it indicates plug time on these. also a few days later it started this fun little lunging thing where the rpms rise up and down while going down the road.
1. I ordered up a set of the sp534s and installed them at .030. thought all was well until a couple days later it started to misfire again. figured maybe it was a bad plug I got. so bought another set reinstalled still no help.
2. figuring the mileage was high i did some research and came to the conclusion that possibly my intake valves are all coked up and needed to be cleaned. I pulled the intake apart and shot some walnut shells at the valves. The only ones that were truly really bad were the front two cylinders where the air tends to not hit directly. Got them all nice and clean.
3. I installed a brand new set of OEM injectors. I replaced all six. Figured while i have everything apart. old injectors looked good nothing to indicate a problem.
After reassembling everything I took it out for a test drive. Still misfiring. also still lunging. Now I was getting confused.
I have done a couple of datalogs after this to try and confirm if anything else was reading off and causing the misfire. Everything reads normal. The car misfires under high load lower rpm sessions. Say accelerating from a yield sign at about 15mph up to 40 with about 25 percent throttle. It will just continuously misfire until you tip into it and get it to downshift and accelerate. The only thing that is evidenced in the logs is the RPM change from the misfire. It runs very strong otherwise with plenty of power. it only does this is this range nowhere else. Also around the 25-45mph if you hold the throttle steady the RPMs will fluctuate up and down about 150-200 RPM. It does this constantly. The Throttle angle actual reflects this on the log as well. You can see it rise up and down with no change from the pedal, only the change from the PCM commanded throttle. It will move as much as 2 degrees on perfectly flat unchanged road. Even with the cruise control on it will not stop the lunging. I do not see anything else moving with this except for boost going up and down maybe. I am using the SCT software to datalog and I have to say the program is a little buggy. but the data doesnt seem compromised just hard to view.
So after doing some more reading and research I figured out that the TIP has a big play in the way that everything works. I know these are Speed Density so there is no MAF or anything like that to skew readings.
4. I loaded up the Stock Tune and then reinstalled the 2 bar map sensor. Went for a test drive and everything seemed ok. then a day later it came back. same things. Misfire and lunging.
5. I took the 3 bar map sensor I had for the tune and placed it in the TIP position. Same part number and everything. No change still misfiring and lunging.
really confused now I am just grabbing at strings.
6. I installed a brand new throttle body with new TPS and Motor. No change still lunging and misfiring
7. I installed 2 fresh wideband OEM Bosch O2 sensors. Runs smoother up top now but still no stopping of the misfire or lunging.
8. I verified and double checked the knock sensor wires even though there is no evidence in the log of them being an issue and the loom is in great shape. no chafing at all.
9. I installed 6 new OEM coils and 6 new spark plugs gapped at .30 then .28. Still misfiring and lunging.
I am just really frustrated at this point as usually I am not this clumsy or lost on a problem like this. I have tried to figure out how the system works and cannot think of anything else causing this issue. There has been NOT ONE check engine light or code set. The PCM thinks everything is peachy. Usually I diagnose and work it out step by step to reasonably determine the underlying cause but I finally am at a loss on this one.
The only variable that has been truly determined is that if you disconnect the battery or do a KAM reset that the problems soften and the progressively get worse. The misfire happens at any time. The fluctuating lunging rpm thing happens worse when it is cold and then gets better as it warms up. like 300 rpm in the morning but then when near work maybe 150rpm. you can almost always get it to misfire in the same speed rpm load range as stated above. Short of replacing the PCM i think I have covered everything that could be related to these instances.
This morning on a whim I disconnected the TIP sensor. It stopped doing the lunging but I could not determine the misfire bit really because of the Limp Mode and wrench light. Plugged it all back in and just went to lunch this afternoon and misfired right out of work and was lunging. It is really annoying to drive at times now. if you punch it while it does this is downshifts and takes off like a bat out of hell. it is powerful and doesn't feel mechanically weak.
PLEASE HELP! I am out of ideas for now. I can post some logs if requested tonight when I get home. Thanks for any help.
