Even if your live-data shows only a couple of parameters at a time, study each and look for weird things happening when the engine is struggling. temperatures should never be changing fast. At idle, TP and MAF should be stable and KNK never detected. MAP is a bit tougher to generalize, but should drop as the engine dies. IAC should show an increase as the engine dies; look for an increase in both the "commanded" position and the actual position reported.
Trouble Code Definitions
Do I have a grounding issue? 07 Ford Freestyle 3.0-V6 w/ 198000 miles
- Thread starter wfsdno
- Start date
@grcauto Should I watch STFT or LTFT trims? Should they be consistant? Something in particular I should be watching for? I will set up that on my way home today. Car did not act up at all on the way to work this morning, It was below 32* this morning. Yesterday on way home I did notice IAT fluctuated with my speed - on the Hwy the temp when down, in town the temp would go up(seems normal?)
Will report back tomorrow with fuel trim info. Thanks!!
Will report back tomorrow with fuel trim info. Thanks!!
nickb2
Wrench. Diagnostic Tech.
I am so sory I dont really have time to respond to this thread, my sister died this week, family is busy, but I had a few video's for your enjoyment if you wish,
This one is a bit complicated but the logic is sound.
This one is a bit complicated but the logic is sound.
nickb2
Wrench. Diagnostic Tech.
this one I really like and have linked to it here before, this guy explains it very well.
Sorry to hear about the loss of your sister.
I will watch the videos above today. The car has not missed a beat in almost 2 days!
I did watch fuel trims and snapped some pictures. I was going about 60 mph when these were taken about 3 seconds apart, slight flucuation in speed (no more that 1 or 2 MPH). Every once in a while I could get a reading where they matched each other.
I do not know how to reset LTFT data. Unplugging the battery for 30 mins?
Hope that helps!
I will watch the videos above today. The car has not missed a beat in almost 2 days!
I did watch fuel trims and snapped some pictures. I was going about 60 mph when these were taken about 3 seconds apart, slight flucuation in speed (no more that 1 or 2 MPH). Every once in a while I could get a reading where they matched each other.
I do not know how to reset LTFT data. Unplugging the battery for 30 mins?
Hope that helps!
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What do you mean by control fuel delivery?
Something weird I have noticed, not sure how much it matters, the stuttering seems worse when the fuel tank is about 3/4 full. I have been under 1/2 tank the last few days and 0 issues in 200 miles.
Watched the second video, interesting. Will watch fuel trims next time out driving.
Thanks for trying to help. May look into vacuum leaks.
Something weird I have noticed, not sure how much it matters, the stuttering seems worse when the fuel tank is about 3/4 full. I have been under 1/2 tank the last few days and 0 issues in 200 miles.
Watched the second video, interesting. Will watch fuel trims next time out driving.
Thanks for trying to help. May look into vacuum leaks.
Ok, so this morning I stopped and put in 5 gals to get to half a tank and before I could hit the road it started to stall and hiccup. It only had the issue for about 10 miles then ran perfectly.
I plugged in the reader and got some readings while this happened. STFT would immediately jump up. It would be reading around +5 and jump to +10 or more and them go right back down to normal. FTFT did not change.
MAP readings were in the 16 - 20 in/Hg (edited for correctness)
MAF readings were in the 2-4 lb/min (edited for correctness)
RPM's at these readings were about 1600- 1650 rpm (edited for correctness)
Neither changed during the issues.
Hope this info helps!
Thanks!
I plugged in the reader and got some readings while this happened. STFT would immediately jump up. It would be reading around +5 and jump to +10 or more and them go right back down to normal. FTFT did not change.
MAP readings were in the 16 - 20 in/Hg (edited for correctness)
MAF readings were in the 2-4 lb/min (edited for correctness)
RPM's at these readings were about 1600- 1650 rpm (edited for correctness)
Neither changed during the issues.
Hope this info helps!
Thanks!
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What are the units for those MAP/MAF readings, and what is the rpm? Get some of the others parameters, like spark advance, KNK, TP, temperatures, injector PW, etc. Did you have a fuel-pressure gauge attached to observe FP during this episode? Is this a return-less fuel system?
Have you tried running with the tank fairly full, but the tank filler-cap loose or off? This problem seems so directly related to the tank level, I am perplexed. Even if there were a leak in fittings/lines on the pump unit (which has been replaced), I would think having all that stuff submerged more would only make things better. I would expect a problem to be worse when the tank level was lower... The one exception is if pressure/vacuum in the tank is abnormal (I would expect only pressure should be there, generally). If a loose cap seems to help, I would suspect the EVAP/purge circus is malfunctioning.
Just kind of guessing now, sorry.
Have you tried running with the tank fairly full, but the tank filler-cap loose or off? This problem seems so directly related to the tank level, I am perplexed. Even if there were a leak in fittings/lines on the pump unit (which has been replaced), I would think having all that stuff submerged more would only make things better. I would expect a problem to be worse when the tank level was lower... The one exception is if pressure/vacuum in the tank is abnormal (I would expect only pressure should be there, generally). If a loose cap seems to help, I would suspect the EVAP/purge circus is malfunctioning.
Just kind of guessing now, sorry.