Engine Running Rough

Discussion in '2005+ Mustang GT 4.6L Tech' started by 08Bullitt_0067, Feb 2, 2020.

  1. 08Bullitt_0067

    08Bullitt_0067 forum member

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    Symptoms: The car seems like it's running down one cylinder. I was driving home two weeks ago and all of the sudden the car started missing and surging at a stop light. A blip of the throttle is followed by a dip in rpm to the point where it feels like it's going to die, then a surge in rpm. Under acceleration, the engine runs smoother, but seems down on power.

    I tried to trouble shoot it today. Cold start it was having trouble immediately. The idle surged and dipped from cold start almost like a vacuum leak. After some warm up, the idle would settle but it was high and a little rough like a miss. I noticed there are time where it sounds like one of the injectors is emitting a high pitched beep/squeak.

    No DTC codes at all.

    I am thinking maybe an injector based on the noise i was hearing? Anyone else ever experience that?

    Mods:
    Whipple SC
    comp 127500 cams
    LTs

    Thanks
     
  2. 07gts197

    07gts197 forum member

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    Do you have a way of datalogging?


    Sent from my iPhone using Tapatalk
     
  3. 08Bullitt_0067

    08Bullitt_0067 forum member

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    I have a mac laptop and android phone. i have an old windows laptop stashed away somewhere that I previously used for datalogging, but i need to dig it up, find the usb chord to hook to the sct x3 and see if it still works.

    Im sure there are better ways to datalog these days. i can research them, but im sure that will be another few hundos to get that set up. that may be worth it in the long run though. I also have limited parameters to monitor on my x3. if those are useful, i can get that info. thanks.
     
  4. 07gts197

    07gts197 forum member

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    I’m not sure what you can datalog on the x3 but at a minimum log throttle position, load, timing, vct, fuel trim and rpms. You’ll find something in there.

    Also you could buy an elm327 dongle and use torque app (I’m a fan of forscan myself) on your phone to datalog.


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    GlassTop09 and nfrizell like this.
  5. Dino Dino Bambino

    Dino Dino Bambino I have a red car

    Age:
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    Check all the intake and vacuum hoses to make sure none are disconnected, cracked, or broken. Same goes with the plugs, coils, and injectors. An ECU scan for fault codes would point you in the right direction but if that draws a blank, you could plug an ELM327 dongle into the OBD 2 port and use a datalogging software (I use Car Scanner Pro ELM OBD 2 on my Android smartphone) to pinpoint the problem. However since the engine is effectively running on seven cylinders, I fear the problem may be more serious if you find there are no misfire codes.
    Pull the plugs and perform a compression check on all cylinders to rule out the possibility of a broken ring land caused by detonation.
     
    Last edited: Feb 3, 2020
  6. slackinoff

    slackinoff Senior Member S197 Team Member

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    The $5 mechanics stethoscope from harbor freight is really great at listening to injectors. You can really hear if they are firing or not.
     
  7. golkhl

    golkhl forum member

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    When is the last time you changed the spark plugs?
     
  8. GlassTop09

    GlassTop09 Member

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    +2 on FORScan. The std license for FORScan is freeware. The extended license (which you have to pay for) will unlock all the bi-directional control & further access to more advanced testing\programming capabilities.

    FORScan is Ford, Lincoln & Mecury specific software so it's dashboard datalogging capabilities is second only to Ford's IDS software.

    Best move I've made for TS'ing my Stang & I'm most likely gonna spring for the lifetime FORScan extended license……………….
     
    07gts197 likes this.
  9. 08Bullitt_0067

    08Bullitt_0067 forum member

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    Thanks for the data logging suggestions. I have a bluetooth dongle on order.

    Great, i'll be picking one of these up.

    Plugs are about 3-4k miles new when I had the new motor put in with the SC.
    Im running about 10lb of boost on a forged motor.
     
  10. 08Bullitt_0067

    08Bullitt_0067 forum member

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    I took some picture of the datalog i did with the sct x3 with the car trying to idle. In all cases, the tp_v value is 0.00. is this normal? If i had to guess this parameter is the throttle position voltage?
     
  11. slackinoff

    slackinoff Senior Member S197 Team Member

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    I seem to recall mine being above zero.

    Sent from my SM-G975U using Tapatalk
     
  12. 07gts197

    07gts197 forum member

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    It should be over zero. Did you try hitting the gas a little to see if it moves?


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  13. Dino Dino Bambino

    Dino Dino Bambino I have a red car

    Age:
    57
    1,834
    479
    At idle the TPS should be around 1.3v.
     
  14. 08Bullitt_0067

    08Bullitt_0067 forum member

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    Maybe this is or part of the issue. I just got the bluetooth odbII dongle today so hopefully ill have some time this weekend to get a datalog.
     
  15. Panchosraider

    Panchosraider Junior Member

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    I had this similar problem, I searched the boards to no avail. So the way i stumbled across the answer was I had accidentally left one of my cam phasers sensors off when I was checking this or that. Started the car and it was magically fixed. Well not exactly, but herein lies the answer. Attempt unplugging your phasers sensors, one bank at a time, this will put your Mustang to default timing if you start your car and the problem ceased you know that there is an issue with the phaser on whichever bank you unplugged. I had a phaser with a sheared indexing pin and it obviously threw my timing to hell. So perhaps you just have a bad phaser or you need full timing done. Wish you the best in getting your pony back up to snuff.
     
  16. Dino Dino Bambino

    Dino Dino Bambino I have a red car

    Age:
    57
    1,834
    479
    Pull the plugs and do a compression check on all the cylinders if you have time this weekend. If you find one cylinder is low, pour a tablespoon of oil down the spark plug hole and repeat the test.
     
  17. 08Bullitt_0067

    08Bullitt_0067 forum member

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    I spent most of the time i had trying to get FORScan to work. Long story short, the custom tune prevents the software from reading all the vehicle info when it connects. The FORScan team helped resolve that. So now I can datalog. What things should I look at and what values are "Normal"? With FORScan Lite, can i record my datalog and export it?

    If I'm still in the same spot this by this weekend, i'll start pulling plugs and go from there. thanks you guys.
     
  18. 08Bullitt_0067

    08Bullitt_0067 forum member

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    Hopefully tomorrow i can get some time on this. What kinds of things should i look for when data logging? If it's too much to explain what "normal" values should be, I will try to post the log here. Are there other resources i can look at to let me know what values and ranges i should expect? Thanks guys.
     
  19. GlassTop09

    GlassTop09 Member

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    Look in this thread at post #10 to use as a guide:
    https://www.s197forum.com/threads/stock-swapped-engine-runs-like-garbage-help.137203/
    For your case, add the TPS% PID (throttle position sensor angle) & TP_V PID (TPS voltage output from TPS) to this list.
    In FORScan, the 1st 12 PID readouts (starting on lft side counting in column, not in row) under the Dashboard Tab can be read in graph form under the Osciliscope Tab as well so the order of PID arrangement can help make the data more relevant.

    PS---Also run the KOEO check test in FORScan before startup as well as run the KOER check test after engine has reached full hot idle to get a log of the component readiness\operation that the PCM does to ensure that all is operational as it will also alert to any issues it finds & report this data in a log that that can be saved. Just follow the prompts that FORScan will give you before you start these tests so that you know of the items that the software will tell you to perform while these tests are being run.

    FYI.

    Hope this helps.
     
    Last edited: Feb 15, 2020
  20. 08Bullitt_0067

    08Bullitt_0067 forum member

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    So after a few weeks of dealing with technical issues with FORScan Lite, getting slammed with work and then a sinus surgery, I was finally able to get a scan with the card idling up to running temp. Also a KOEO and a KOER test.

    First obvious things i noticed:
    1. At startup, FUELSYS1 is Closed Loop, AND it goes in an out of CL - Fault
    2. FUELSYS1 goes into Open Loop, then OL - Fault and stays there.
    3. FRP_REL - fuel rail pressure fluctuates between 38.5 to 40.5. (not sure this is normal, but adding this for the KOER results).
    4. O2S11 - O2 Sensor Bank1, sensor1: This sensor ranges from 0.00 to 0.81 V while P2S21 reads between 0.07 to 0.08V. I wonder why the huge Voltage range with the Bank1 sensor?
    4. No DTC codes
    I have all the other ODBII Pid data, but don't know what's off.

    KOEO - test results in no issues.

    KOER - Resulted in multiple codes:
    P1101 - "MAF Sensor Out of Self Test Range". I'll be checking for leaks again. I had already taken the MAF intake off a few weeks ago to inspect and didn't find anything.

    P1127 - "Exhaust not warm enough, downstream HO2S not tested". I think this may be tune related... no cats, but pass ODBII inspection.

    P2195 - "HO2S11 not switching correctly. Sensor indicates lean". This indicates possible low fuel pressure, which is why i added the fuel rail pressure above.

    P2197 - "HO2S11 not switching correctly. Sensor indicates lean". This indicates possible low fuel pressure, which is why i added the fuel rail pressure above.

    If I'm reading into these correctly, I think i may have a vac leak somewhere or some un-metered air getting in. I have the full log files and the test result files if anyone is interested. Or any other suggestions or PIDs values you'd like to see?
     
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