One bank shows rich on WB with slgiht engine vibration

+ Reply to Thread
Page 1 of 5 12345 Last
Results 1 to 15 of 67
  1. #1

    Icon5 One bank shows rich on WB with slgiht engine vibration

    The car has developed a slight vibration when running and reviewing the O2's one bank shows the O2's at 14.5-15.0 (normal readings) while the other runs 13.0-13.5 (not normal). There is a WB on each bank so I can see this and it clearly acts like one cylinder isn't working properly.

    I pulled plugs last weekend and nothing stood out indicating which cylinder(s) were the culprit and the NOID lights indicate that electrical signals are getting to the injectors.

    So, what's the best method to determine which cylinder is acting irrational? I have an MSPro for management and I've logged the engine running but I'm not sure what to review in the logs to see what's going on in each cylinder. Help?

    ks
    Last edited by KEVINS; 08-19-2020 at 08:32 AM.

  2. Remove Advertisements
    ModularFords.com
    Advertisements
     

  3. #2

    Default

    Unless you have a Wideband or an EGT probe on each exhaust I don't think you are going to get cylinder by cylinder fueling or temperature (which is a fueling indicator) data on a cylinder by cylinder basis. Because you are reporting a 14.5 to 15.0 AFR on one bank I a presuming this is an idle condition, Kevin. Am I correct?

    If it is idle and the other bank is running rich (13.0 ro 13.5 AFR) I would suspect something in the injectors. How old are they and when was the last time they were cleaned?


    Ed

  4. #3

    Default

    That's what I thought, I was hoping for a miracle...

    Yea, those O2's are at idle. They are a flowed/matched set of 160lb Inj's I bought brand new 3 years ago and now have less than 300 miles on them, mostly E85. I'll pull them when I get time and get with my tuner. He mentioned something about "let's flow test them" so maybe he has something to check/clean them with.
    If I have to send them out for testing any idea what that would/should cost?

    ks

  5. Remove Advertisements
    ModularFords.com
    Advertisements
     

  6. #4

    Default

    I haven't done any this year so this is year old sort of data but the price was $100 for most shops. You want them to do an ultrasonic cleaning. Most of the shops use an ASNU machine to do the actual cleaning.

    Ed

  7. #5

    Default

    If I have to send them out I'll send them to the company that I bought them from.

    I have new s-plugs coming this week and I thought I would toss them in and let it idle for about 10-15 minutes then pull them. Maybe something will be noticeable hinting at the culprit cylinder.

    ks

  8. #6

    Default

    Kevin
    Switch one fuel injector at a time from bank to bank and log your A/F at idle after each swap noteing which cylinder each came from and which it goes into. If/when the rich condition jumps to the opposite bank you will know which cylinder the injector came from. This should also give you an idea if the issue is something other than an injector if the condition never jumps from one bank to the other even after all have been swapped side for side.

    Ken
    Last edited by 4sdvenom; 08-25-2020 at 11:55 AM.

  9. #7

    Default

    Thanks Ken,
    I thought of that but that is a LOT of work. It takes about 45 minutes to pull the rails off then another 45min to put them back on and this would have to be done each time. Not impossible, but a full days work that I don't have time for right now. It may come to that but it may be next year if it does.

    ks

  10. #8

    Default

    Kevin, is your entire fuel system ethanol ready?

    If there is a component somewhere that is not, the ethanol will slowly deteriorate that component over time. The deterioration from the component will not make an injector flow more but it will make an injector flow less. If the ECU tries to compensate for the reduced injector flow by increasing pulse width the obstructed injector might be able to be made to perform close to the commanded fueling but the other injectors will run rich at that pulse width. Sort of convoluted thinking but a possibility.

    The fix would be an injector cleaning and a fuel system health check and tune up. Sometimes the crud can come from a fuel pump or other component (fuel lines?) that is not ethanol ready.


    Ed

  11. #9

    Default

    Yes, it's all E85 ready: pumps, fuel filter, fuel lines, regulator, etc.

    If a bank is running RICH wouldn't that mean an Inj is spraying too much? If so, this seems unlikely but I'm not sure what the logistics are when the MSPro is commanding a certain AFR and either:

    1. A plug doesn't fire.
    2. An injector is not acting correctly,either being plugged or spraying too much..somehow. It seems logical that the ECU is commanding more fuel and and one Inj is plugged then the other inj's are making up for it causing a rich condition..?? weird but possible.

    All I know is that one bank is reading rich at 13.2ish and the engine has a slight vibration.

    I had to send back the spark plugs I ordered through Amazon b/c I only received 7 and there was no way to contact them about it. So I sent them back for a refund and will have to get 8 more, probably locally this time.

    ks
    Last edited by KEVINS; 08-25-2020 at 01:56 PM.

  12. #10

    Default

    What the banks do is dependent on which bank the ECU is attempting to correct for. If it is correcting for the lean bank when it begins to richen the AFR to come back to the commanded AFR it will cause the opposite bank to go rich because the correction is made across all the injectors not cylinder by cylinder. I seem to recall a cylinder by cylinder capability built into the MS3Pro s/w but don't remember off the top of my head how to turn it on or what it requires to be operational. I'll dig around a bit tonight and see what I can turn up.


    Ed

  13. #11

    Default

    I thought I would give a slight update on this. I figured out a way to verify each injector and spark for each cylinder. I simply watched the O2's then unplugged an injector or coil wire. If they were working then O2's would jump from 14 to 16 when unplugged.

    When I got to #5 coil I unplugged it and O2's never changed. I did this about 10 times and verified all injectors/coils on all banks worked but this coil clearly wasn't doing anything.
    So I swapped the #5 coil and #6 coil to see if it was the wiring or the coil but when I swapped them then both coils stopped working (!) and this is as far as I got tonight.

    Maybe something in the wiring for the #5 coil is bad and burned up both coils, I'm not sure yet. I will find that youtube vid that shows how to test the coils then see what I come up with. Tracing the wiring won't be easy since I tucked all the wires under the manifold.

    ks

  14. #12

    Default

    Interesting. A dead coil would certainly produce a similar experience. I was so injector focussed I completely overlooked the coils. Excellent Sherlock Holmes work by the way.


    Ed

  15. #13

    Default

    A little update..
    During Spark Testing the MSPro I discovered that the coil for #5 cylinder got HOT and started melting the coil housing with Key On. This explains why coils plugged into that connector would fail afterwards.

    I thought that there must be a shorted wire against the block or something for #5 cylinder so at the coil connector I tested to see if the wires were shorted but it didn't indicate there was a short with key-off.

    1. I sent Matt at DIY an email to see if there is a method to trouble shoot the MSPro/Quadspark.

    2. I also sent John at J&S to see if there is a way to troubleshoot the wiring from the knock system. I know that the Vampire can be unplugged and a bypass connector added to the harness (this comes with the kit) but I'm not sure if this will troubleshoot the wiring. The harness is all p-n-p connectors.

    I'm not sure where to go from here. I did order a new Quad Spark but not sure what to test to see if this is the culprit or something else is causing the issue.

    I suppose I could use the by-pass connector at the Vampire then turn key on and see if there is voltage at the coil connector but I'm not sure exactly what this would tell me:

    No voltage = Vampire Bad..?
    Voltage = MS or QS bad..?


    ks

  16. #14

    Default

    I am not electrically smart, Kevin. That said, I would stay close to Matt re trouble shooting. His vantage point gives him the best chance of having run into this previously, which makes hem likely the best trouble shooting coach.

    Ed

  17. #15

    Default

    John at J&S just got back with me and said that the Vampire system only works when knock is present so pointed me to the MS. I will verify voltage by bypassing the Vampire with the bypass connector. I will bypass the Vampire then turn the key on to see if there is any voltage across the #5 coil connector. Can I assume that the voltage across the coil connector can only get up to 12V? It should read 0V with key on but my guess it will show voltage.

    ks

  18. Remove Advertisements
    ModularFords.com
    Advertisements
     

+ Reply to Thread
Page 1 of 5 12345 Last