Bringing TBI and Multi Port Fuel Injection to a New Level.     EFI Conversions and Tuning! Seattle to Portland! E-mail Tuning Consultant!
Results 1 to 14 of 14

Thread: 1986 TPI Corvette intermittent code 33 - TunerPro RT

  1. #1
    Electronic Ignition!
    Join Date
    Apr 2018
    Location
    Gainesville
    Posts
    10

    1986 TPI Corvette intermittent code 33 - TunerPro RT

    I have an 1986 Corvette vert (alum. heads) 2.73 rear end with a 1227165 ECM that has a Hypertech thermomaster (original AANK) for auto tranny and AL heads. Before you go off on hypertech ... I was sort of forced into it since the stock proms were just not available. Hypertech cured my problem and keeps my engine running cool.

    I have an intermittent code 33 on my car that I haven't been able to catch on turnerpro rt which I just got running using a 1320electronics bluetooth adapter -)> only 160 baud.

    I don't have any experience scanning but the few times I scanned my car this last weekend. I used an adx file from someone on corvette forum that seem to let my system work.

    What things might I be monitoring that would be important for a code 33 (Maf High)? Is it appropriate to post scan files or recordings here to get others opinions?


    Here's a link to a scan file:

    https://drive.google.com/open?id=1Iq...vD7T8F9jy0YV9e
    Last edited by rharker; 04-09-2018 at 04:53 PM. Reason: added file link

  2. #2
    Fuel Injected! tamperedchevy's Avatar
    Join Date
    Mar 2014
    Location
    Missouri
    Age
    31
    Posts
    69
    my intermittent code 33 ended up being a bad map connector. couple dollar ebay fix. might not be your problem. check connectors, maybe a short(which is hard to trace til it fails compldetely) make sure the maf ground is good and going to the other sensor's and ecm's ground. i heard they should be grounded in the same spot

  3. #3
    Electronic Ignition!
    Join Date
    Apr 2018
    Location
    Gainesville
    Posts
    10
    Quote Originally Posted by tamperedchevy View Post
    my intermittent code 33 ended up being a bad map connector. couple dollar ebay fix. might not be your problem. check connectors, maybe a short(which is hard to trace til it fails compldetely) make sure the maf ground is good and going to the other sensor's and ecm's ground. i heard they should be grounded in the same spot

    Thanks - I'm quite sure that I have some bad wiring around the fuel pump relay and battery area which I believe is involved with the 2 MAF relays. It had some pi$$-poor splices put in there ... I already replaced one. I might need to buy another pigtail for the fuel pump relay to do it proper. Today it finally set the code again on the 4th day of driving but I didn't have my laptop with me. Friday I'll have some time to t-shoot.

    Anyone have the BIN file for an AANK? It's not in the list here. I'm just curious what the difference between a Hypertech thermomaster and the stock prom.

    Thanks,
    Robert
    Last edited by rharker; 04-11-2018 at 06:11 AM.

  4. #4
    Electronic Ignition!
    Join Date
    Apr 2018
    Location
    Gainesville
    Posts
    10
    So I got a chance to datalog again this time with it driving and the code 33 active. I noticed that the airflow was behaving weird going high sometimes when the RPM was low and going low sometimes when the RPM was higher (thus the error code). I'll post the log tonight and maybe somebody can help me tell what it means. I still got to clean up my wiring.

  5. #5
    Fuel Injected! steveo's Avatar
    Join Date
    Aug 2013
    Posts
    2,450
    maybe the maf is dying, if you tap on your maf with a screwdriver handle or something while the car is running, does the engine stumble?

  6. #6
    Electronic Ignition!
    Join Date
    Apr 2018
    Location
    Gainesville
    Posts
    10
    Quote Originally Posted by steveo View Post
    maybe the maf is dying, if you tap on your maf with a screwdriver handle or something while the car is running, does the engine stumble?
    I'll try that ... thanks.

    Robert

  7. #7
    Electronic Ignition!
    Join Date
    Apr 2018
    Location
    Gainesville
    Posts
    10
    https://youtu.be/_xtNXAZzV5s

    Youtube vid of my drive scan run.

  8. #8
    Electronic Ignition!
    Join Date
    Apr 2018
    Location
    Gainesville
    Posts
    10
    UPDATE --
    Someone pointed out to me that the Hypertech chip that I have is actually based upon an AANL (from the log files) instead of the stock equivalent AANK .... would that cause any issues?

    Also the code 33 is no longer intermittent ... it comes ~5 seconds after start every time. The only thing that I notice for drive-ability is that when letting off the gas almost every time there is a slight hesitation or stumble. The displayed MPG is comparable to when it was running no codes at 16 in the city ~24 on the highway.
    Last edited by rharker; 04-23-2018 at 07:42 AM. Reason: added details

  9. #9
    Electronic Ignition!
    Join Date
    Apr 2018
    Location
    Gainesville
    Posts
    10
    The codes degraded to 33 and now 34 so I installed a new MAF which did not help although it went back to only code 33. Somebody suggested that I upgrade my ECU to an 87-89 memcal so that my computer will communicate at 8192 baud instead of the agonizingly slow 160 baud I have now. So I'm looking for a 87 vette Memcal ($32B) for and automatic with 3.07 gears. Would someone be able to burn one for me?

  10. #10
    Super Moderator dave w's Avatar
    Join Date
    Feb 2011
    Posts
    3,800
    Quote Originally Posted by rharker View Post
    The codes degraded to 33 and now 34 so I installed a new MAF which did not help although it went back to only code 33. Somebody suggested that I upgrade my ECU to an 87-89 memcal so that my computer will communicate at 8192 baud instead of the agonizingly slow 160 baud I have now. So I'm looking for a 87 vette Memcal ($32B) for and automatic with 3.07 gears. Would someone be able to burn one for me?
    I can help you with an 87 Vette Memcal. Please send me a Private Message (PM) for details.

    dave w

  11. #11
    Carb and Points!
    Join Date
    Oct 2018
    Age
    44
    Posts
    3
    if theres a MAP code on a MAF car i would say wrong computer? or prom

  12. #12
    Electronic Ignition!
    Join Date
    Apr 2018
    Location
    Gainesville
    Posts
    10
    Quote Originally Posted by METALMAN1972 View Post
    if theres a MAP code on a MAF car i would say wrong computer? or prom
    I forgot about this forum and I failed to follow up ... my bad. The MAF codes were cleared by installing new MAF relays (burnoff & power) my 3rd set. I have the blank Memcal that I intend to get burned so that it has the faster baud rate other than the 160 I have now.

    Thanks,
    Robert

  13. #13
    Fuel Injected!
    Join Date
    Nov 2013
    Posts
    158
    Move to the last Y-Car calibration. 1989 Y-car automatic trans. Disconnect the Cold Start injector.
    Attached Files Attached Files

  14. #14
    Electronic Ignition!
    Join Date
    Apr 2018
    Location
    Gainesville
    Posts
    10
    Quote Originally Posted by billygraves View Post
    Move to the last Y-Car calibration. 1989 Y-car automatic trans. Disconnect the Cold Start injector.

    Thanks Billy this will help out a lot!

Similar Threads

  1. New person here ... 1986 Corvette - Using Tunerpro RT
    By rharker in forum Introductions
    Replies: 0
    Last Post: 04-09-2018, 01:03 PM
  2. Replies: 4
    Last Post: 06-14-2017, 11:18 PM
  3. Code 36 in 1987 Corvette
    By puzzigully in forum GM EFI Systems
    Replies: 3
    Last Post: 06-04-2015, 04:32 PM
  4. Intermittent Acceleration Issue - TunerPro file attached
    By az79k5project in forum GM EFI Systems
    Replies: 1
    Last Post: 07-27-2014, 07:07 AM
  5. 87 Corvette New to TunerPro RT
    By 1987 C-4 Corvette in forum GM EFI Systems
    Replies: 5
    Last Post: 04-03-2014, 08:18 AM

Tags for this Thread

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
  •