Bringing TBI and Multi Port Fuel Injection to a New Level.     EFI Conversions and Tuning! Seattle to Portland! E-mail Tuning Consultant!
Page 1 of 2 12 LastLast
Results 1 to 15 of 19

Thread: 4L80 acting weird AFTER adding wire for TCC

  1. #1
    Fuel Injected! CDeeZ's Avatar
    Join Date
    May 2012
    Location
    Jokelahoma
    Posts
    408

    4L80 acting weird AFTER adding wire for TCC

    I have been driving my 4L80 around without the TCC wired up. Last night, I wired in the TCC.

    I swapped in the 7427 PCM in this truck a few years back and everything was ok then.
    I also wired it just as is described in the conversion thread here: http://www.gearhead-efi.com/Fuel-Inj...php?t-173.html

    The truck USED to have a 700R4 so when I swapped in the 7427 a few years back I put the Orange wire from the brake switch to pin E13 at the PCM: E13--------Orange-----------Battery (Inputed in place of Brake Switchfor TCC to function)

    Now last night I started tracing the Purple wire from the brake switch and found that it in fact does go to a diode module under the dash for the ABS system. I deleted the ABS system on this truck... So what I did was i cut the one purple wire going FROM the brake switch TO the ABS diode module and I pinned that purple wire into pin E13 in place of the orange wire that WAS there.


    This trans has worked flawlessly so far, albeit running without the TCC functioning. There is a big cooler setup on it that I borrowed from a SuperDuty F250 or F350 so I don't think it was ever getting very warm.

    Took it out for a test today and it felt weird like either the converter was locking and unlocking -AND/OR- the trans was hunting between 3rd and 4th gear.... BEFORE I captured the log I'm posting, I was driving and when the TCC locked in what I think was 3rd gear, I could tap the brake switch and make it unlock/lock like you would expect. However, I soon realized an issue, which I DID capture with the attached log.

    If you start this log at 44 seconds in you can then shortly thereafter see it hunt between 3rd and 4th and it even loses the data stream connection at least once around this time also.......

    In this trans ADX the TPS shows 22%, but if I switch back to the regular ADX, the non transmission one it shows what the TPS ACTUALLY IS, which is nowhere near 22%, more like 0% or 1.2% max (my throttle is a bit sticky lol) COULD this ADX be screwed and the erroneous TPS reading be causing this issue????

    I have been scanning the trans using the
    A220 Trans1 $0E TP5 v250.adx.... The 2nd one doesn't seem to offer much or do anything?

    I found this thread where Billy is talking about no using the brake switch for the TCC (post #3):
    http://www.gearhead-efi.com/Fuel-Injection/showthread.php?4128-TH400-to-4L80E-swap-and-1227747-to-16197427-swap

    ANd this one where Dave is talking about a relay???? I thought the relay was only for if you are swapping from 4L60e to 4L80e??? (post #16)
    https://ck5.com/forums/threads/compu...o-help.295902/
    Attached Files Attached Files
    Last edited by CDeeZ; 1 Week Ago at 12:38 PM.

  2. #2
    Fuel Injected! CDeeZ's Avatar
    Join Date
    May 2012
    Location
    Jokelahoma
    Posts
    408
    Here is how I wired the TCC as per the 6395 PCM...
    Attached Images Attached Images

  3. #3
    Fuel Injected! CDeeZ's Avatar
    Join Date
    May 2012
    Location
    Jokelahoma
    Posts
    408
    No one? I readjusted the brake switch and confirmed that it has power ON brake OFF and power OFF brake ON at the respective TCC pin E13... The TCC seemed to unlock correctly at lower speeds as I said, but once I kept going it started acting real werid when it was locking up in 4th.

    Guess if I can't get this working like GM intended it I will either not run a TCC at all, or, wire the TCC into a toggle and control in manually.

  4. #4
    Fuel Injected! sturgillbd's Avatar
    Join Date
    Jun 2012
    Location
    Big Stone Gap, VA
    Age
    45
    Posts
    459
    Are you using E11 for your TCC? There are two different TCC outputs on this PCM and it all depends on which Mask and transmission you use.

  5. #5
    Fuel Injected!
    Join Date
    Aug 2012
    Posts
    344
    Have you modded any of the lock unlock speeds. Years ago I was fooling with numbers and had that lock unlock problem. Turned out for me if you violate the spread/hysteriasis that can be a problem. Once I corrected things have been fine for years.
    6395, BHDF, 7.4 BBC lightly modded now 6395 BMHM back to BHDF

  6. #6
    Fuel Injected! CDeeZ's Avatar
    Join Date
    May 2012
    Location
    Jokelahoma
    Posts
    408
    I have the brake signal pinned into E13 just like in that diagram above. I have not modified any of the TCC paramteres in the BJDR bin.

    I have been driving it with and without the brake signal pinned in to that spot. The NEW issues is present either way so it must be unrelated. It locks and unlocks correctly when I tap the brake pedal with the wire pinned in. Whatever this newest issue is I'm guessing is unrelated to the TCC since the issue is there with or without the TCC brake signal wire there... I pulled the fuel pump out and the fitler/sock was filthy so I replaced it but no difference. Making 27 or so PSI idle, but I can't see the gauge driving so I don't know if that's an issue.

    I'm wondering if the plugs are fouled again causing this new issue. I can see most all of the sensors spike down to 0 in a datalog when this issue happens. Battery voltage stays the same.

  7. #7
    Fuel Injected!
    Join Date
    Aug 2012
    Posts
    344
    Just for clarity you do have the wire from the tcc solenoid going to E11 so that the pcm grounds it, right
    6395, BHDF, 7.4 BBC lightly modded now 6395 BMHM back to BHDF

  8. #8
    Fuel Injected! CDeeZ's Avatar
    Join Date
    May 2012
    Location
    Jokelahoma
    Posts
    408
    Pin S from the 4L80 for the TCC PWM is going to E11 on the PCM, yes

  9. #9
    Fuel Injected!
    Join Date
    Aug 2012
    Posts
    344
    Re reading your post about tcc locking in 3rd, I don’t think I have seen any $OE that locks in 3rd. Years ago I did fool with using unused tow/haul numbers from $8D I think. I ended up just putting a auto/manual system in for when I wanted it locked when the pcm didn’t. Getting back to your problem it smells of flakey ground, something loose some place.
    6395, BHDF, 7.4 BBC lightly modded now 6395 BMHM back to BHDF

  10. #10
    Fuel Injected! CDeeZ's Avatar
    Join Date
    May 2012
    Location
    Jokelahoma
    Posts
    408
    Yeah, I just thought that wiring in the TCC must have screwed something up cause that's when my newest problem showed up that I've described lol. I now know that isn't the case cuz like I said I pulled the brake switch wire back out and ran it without the TCC and it's still doing it.

    Well, I wonder what ground?? There are the two that go on the intake manifold and I checked them last night. I made bigass grounds out of battery cables that connect block,frame,body so I think it should be better grounded than the factory set it up... Unless there are other grounds to the PCM that I don't know about, I think those two that go on the intake are the only ones though?

    I have been battling the overrich problem for a while trying to get a handle on the best approach and I have fouled plugs twice before. I pulled the plugs out just now and they are pretty fouled again, sooty black on the insulator nose of each plug, some worse than others. I'm going to tape the threads of the plugs and throw them in the blast cabinet and clean them up and put them back in, had good luck with that previously. If I barely touch the gas when accelerating it seems to not be an issue as much, less demand on the already fouled plugs perhaps?

  11. #11
    Fuel Injected!
    Join Date
    Aug 2012
    Posts
    344
    Regarding rich, any chance your reported water temp is not going above your cold enrichment table and so always thinking it should have the (choke) on.
    6395, BHDF, 7.4 BBC lightly modded now 6395 BMHM back to BHDF

  12. #12
    Fuel Injected! CDeeZ's Avatar
    Join Date
    May 2012
    Location
    Jokelahoma
    Posts
    408
    I think I have made some progress on the rich issue. After fiddling around with the injector flow rate what seemed to help the most was to take the VE cell that it idles in, and the surronding cells for I believe 12 in total and reduce them all by a value of 25.

    The other strange issue is still present. I'm still suspecting something with the 4L80. You mentioned a possible ground issue, wouldn't that show up in the scanner on the monitors as some form of a voltage drop, even for a split second? Voltage is rock steady. Tonight, for the second time the PCM set error code 73 Pressure Control Solenoid. Maybe this is the problem???? To describe the issue again, it feels like the trans drops in and out of gear, or hunts between gears when it is happening. I think I've even seen the scanner show it flip between 3rd and 4th when this is happening.....


    EDIT: I can look at older logs and there is SOMETHING displayed on the monitors for the force motor duty cycle.... The log from tonight and the other night when this issue started, NOTHING for force motor duty cycle.
    Last edited by CDeeZ; 1 Week Ago at 08:33 PM.

  13. #13
    Fuel Injected! CDeeZ's Avatar
    Join Date
    May 2012
    Location
    Jokelahoma
    Posts
    408
    The first image is what I would expect the force motor to look like on the logs. (The teal line) This is from a previous log before this issue happened.

    The second image is of the force motor completely spiking down to zero on the monitors, perhaps a sign it's failing? This log is from a few days ago.

    THe last image is showing the force motor duty cycle staying at 0... Doesn't even show up on the monitor now since it's 0. This log is from tonight.
    Attached Images Attached Images

  14. #14
    Fuel Injected! Terminal_Crazy's Avatar
    Join Date
    Oct 2015
    Location
    Lancashire England
    Posts
    302
    Hi
    [QUOTE]
    The second image is of the force motor completely spiking down to zero on the monitors, perhaps a sign it's failing? This log is from a few days ago.[\QUOTE]

    I don,t know and could be wrong but i suspect the log is showing the “commanded” output from the pcm rather than the actual output of the motor. Ie the log is showing pcm output rather than input data.

    Mitch
    '95 Z28 M6 -Just the odd mod.
    '80 350 A3 C3 Corvette - recent addition.

  15. #15
    Fuel Injected! CDeeZ's Avatar
    Join Date
    May 2012
    Location
    Jokelahoma
    Posts
    408
    I think you may be right. I read somewhere that the PCM will shut the force motor off defaulting to max line pressure.

    Where does the 4L80 ground??? Or is it the solenoids grounding as provided by the PCM for each shift event?

Similar Threads

  1. 4l80 pmc tune
    By honsolow in forum OBDII Tuning
    Replies: 2
    Last Post: 09-30-2018, 07:04 AM
  2. $31 / $0E 4L80 tables
    By V8Astro in forum GM EFI Systems
    Replies: 2
    Last Post: 11-24-2015, 11:27 AM
  3. Replies: 5
    Last Post: 01-09-2014, 09:05 PM
  4. TBI acting like a carb with maladjusted float.
    By 1BadAction in forum GM EFI Systems
    Replies: 8
    Last Post: 06-18-2013, 06:32 AM
  5. Red wire and white wire on ALDL???
    By Blazer3664 in forum GM EFI Systems
    Replies: 2
    Last Post: 01-06-2013, 03:53 AM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •