Announcement

Collapse
No announcement yet.

TPS signal to Transmission ECU

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • TPS signal to Transmission ECU

    I have seen different information about splitting the TPS signal. I have a 4L70E transmission and according the installation instruction for the trans it is ok to split the signal. Is it ok to do it this way? "simply splice the yellow/black tps signal wire from the tps connector in the trans harness into the engine harness tps signal wire. Do NOT connect the 5v+ or the sensor ground wires between the harnesses. The engine controller will provide the needed tps voltage

  • #2
    What transmission controller are you using? You can only tap the TPS signal if the trans controller does not influence the signal in any way. Not all trans controllers are created equal and some trans controllers will make TPS read higher than 0% when your foot is off the accelerator pedal which is a total no-go for Pro-Flo 4. If the signal is pulled up, the engine will run poorly.

    We have been suggesting that Pro-Flo 4 customers use the HGM Compushift trans controller because it gets all the sensor data it needs from the CAN bus data stream network without needing to tap any sensors. It's just a simple plug and play deal.

    Comment


    • #3
      I have the Chevrlot Performance Super Matic Controller kit 19332775 that they sell specific for that trans with Trans Control Unit #19332776

      According the installation manual for the controller there is no need to calibrate the TPS signal.

      Note: These transmission controller kits require the use of a Throttle Position Sensor as all shift points and pressures
      are determined from driver throttle input. The Holley TPS kit must be installed on the Holley Carbureted crate engine
      and the harness will plug into the sensor. Sensor adjustment is not critical but must have reasonable range. Visually
      centering the sensor on the bracket and making sure the sensor does not “bottom out” at either end of the throttle range
      is all that is needed. The controller will self-calibrate the sensor range once you power it up. Ramjet engines will use the
      single TPS signal wire from the engine harness (see detail below).
      Last edited by Novalink; 09-12-2019, 10:52 PM.

      Comment


      • #4
        I've seen the TPS tap problem fixed by adding in a diode in series with the TPS tap. I'm sure you're familiar with the really small ATM sized fuses - well they make a diode in the same size/shape. You could pick up an inline ATM fuse holder and put it ahead of the TPS tap wire where it connects to the actual TPS wire. I would also get a short TPS extension harness that way you can tap into the extension harness and not the original wiring in the Pro-Flo 4 harness. Install the extension harness, tap the TPS wire with the fuse holder and install a ATM sized diode. In my experience before, this resolved the TPS problem with the Pro-Flo 4 however on the PCS trans controller side, there was still some kind of weird signal noise problem. I don't know if this was something related to this particular install but it's something to be aware of.

        Comment


        • #5
          I'm having an issue now with my EZTCU controller. Since it seems that it also provides a 5V/ground/ref , the PRO-FLOW 4 is affected by it. I tried using just part of the circuit but the TCU won't have any of it..the PRO FLOW reads 200-300 rpms higher which seems to take it out of idle into cruise settings...I had been using the tcu with a carb n just splurged out to get the PF4 so I'm must work this out...don't know yet if they would be willing to do CAN stuff, they do have some connections ready n labelled as such. Nate in gonna try to find that diode thing n try that out...

          Comment


          • #6
            Found it if this is...now i need to figure iut how to hook it up...n order it...
            You do not have permission to view this gallery.
            This gallery has 1 photos.

            Comment


            • #7
              I would use something like this: https://www.summitracing.com/parts/cei-108103

              I would not cut or splice into any wiring or modify the wiring harness in any way. You can add in that TPS breakout harness and then add in the diode to the one TPS wire. You don't need the 5v or sensor ground wires - just the one TPS wire. I would just wire in a mini fuse holder inline with the TPS wire. Bias the diode so the "arrow" points to the TCU. The issue I've seen isn't rpm related. It's that the TPS reading is pulled up and that's what kicks the Pro-Flo 4 ECU out of idle mode.

              Comment


              • #8
                Thanks for the replay and suggestions...by the way the kit I got came with an extension harness for the tps that looks almost like that except for the extra three wires...as soon as I get to try it with the diode I'll let everyone know how it works...by the way I talked to TCI n they weren't very keen to help with CAN communication issue..I sure wish I could figure it out...I ain't giving up yet.thanks again...

                Comment


                • #9
                  That EZ TCU is a FAST product and as such, it already comes with plug and play compatibility with FAST ECUs using their CAN data stream. There are usually two ideologies when doing CAN support: 1) support only your own stuff or 2) support everyone else's stuff. When you do #1, you create a sort of "ecosystem" of interconnectability between different products and a potential customers is incentivized to purchase and use only those products that work together. So you wind up buying a FAST EFI system and a FAST/TCI trans controller and a FAST this and a FAST that because it all just works together. They really have no incentive to make their CAN work with other stuff because they'd prefer that you only buy FAST stuff. It's a way of choosing to do business and many companies have gone this route.

                  When you buy an HGM CompuShift trans controller, it's configurable to work with any CAN data stream. HGM is only in the business of selling transmissions controllers so the more different systems they can cater to, the more systems they'll sell. Again, just a different way of choosing to do business. I won't fault FAST/TCI for not wanting to expand their CAN because they already have their CAN ecosystem and it's intended to include only their products.

                  Comment


                  • #10
                    Which was my intention..but 5 years n not been able to come up with enough money to get the reat of the stuff even though i bought their XIM for my ls.. i took the plunge with your set up n im happy so far...dollar wise n your support is amazing...to show you I've been around for a while i bought an edelbrock intake for sbc 4 my nova in early 1980...still got the nova...

                    Comment


                    • #11
                      Originally posted by Nate S View Post
                      I've seen the TPS tap problem fixed by adding in a diode in series with the TPS tap. I'm sure you're familiar with the really small ATM sized fuses - well they make a diode in the same size/shape. You could pick up an inline ATM fuse holder and put it ahead of the TPS tap wire where it connects to the actual TPS wire. I would also get a short TPS extension harness that way you can tap into the extension harness and not the original wiring in the Pro-Flo 4 harness. Install the extension harness, tap the TPS wire with the fuse holder and install a ATM sized diode. In my experience before, this resolved the TPS problem with the Pro-Flo 4 however on the PCS trans controller side, there was still some kind of weird signal noise problem. I don't know if this was something related to this particular install but it's something to be aware of.
                      Hi Nate, some feed-back on Your advise. I got my Proflo4 some weeks ago and have now made my first test run. The solution with the diode works perfect, thanks!!. First I got some minor noise problems but I changed the TPS sensor and got a clean signal and the Chevrolet trans controller acts exactly like before without problems

                      Comment


                      • #12
                        Hi Nate, some feed-back on Your advise. I got my Proflo4 some weeks ago and have now made my first test run. The solution with the diode works perfect, thanks!!. First I got some minor noise problems but I changed the TPS sensor and got a clean signal and the Chevrolet trans controller acts exactly like before without problems
                        Novalink- I'm facing the same problem. Is there any way you can please tell me where you got your diode from and what the specs are on the diode as I have no idea where to get one or what to ask for? Also, did you hook up all 3 wires from the TPS or just the signal wire? I'm using an MSD TCU. Thanks in advance!

                        Comment

                        Working...
                        X