86technica Posted January 1 Report Share Posted January 1 I have a 86 technica with an mpi, single coil turbo and intercooler upgrade, the problem I’m having is while getting the inside all back together and ready for the dash to go back in but the harness that connects to the digital cluster also connects to the stock ecu or harness aswell the fuel pump wire for the painless performance cirkit 70113 wiring/fuse kit I also notice the there a few sensors/relays Ill need in the engine bay, will I need to run the stock ecu and harness next to the aftermarket one? One brain for all the aftermarket stuff and tunning and one for the relays and stock stuff is what I’m thinking I forgot to mention I have the stock ecu and harness pulled out of the car Quote Link to comment Share on other sites More sharing options...
tux Posted January 2 Report Share Posted January 2 there are a few wires in the stock harness that you need. Like coolant temp sensor. I don't really remember all the ones needed, maybe also for the a/c. But if you cross reference with the manual, you should be able to figure it out. The ECU only controls fuel, so you don't need to piggyback. I kept the original relay for the ecu/fuel pump. You can replace it if you want. The relays under the hood don't attach to the ecu. Make sure you keep the body harness though. Quote Link to comment Share on other sites More sharing options...
TSITy Posted January 2 Report Share Posted January 2 The technica cluster does not need any signals from the ECU. I can provide you the entire pinout and schematic that I have drawn up, although the colors may be inaccurate as I put it in an 87. It is currently unfinished. I converted my car from analog -> digital gauges and still need to finish the HVAC patch cable that I've been putting off, but the rest of it is finished and confirmed working. When this is done completely, I will be posting the schematics for free for anyone to use (unlike a lot of people who have charged for these things in the past). I can send you the unfinished one if you'd like 1 Quote Link to comment Share on other sites More sharing options...
86technica Posted January 2 Author Report Share Posted January 2 5 hours ago, tux said: there are a few wires in the stock harness that you need. Like coolant temp sensor. I don't really remember all the ones needed, maybe also for the a/c. But if you cross reference with the manual, you should be able to figure it out. The ECU only controls fuel, so you don't need to piggyback. I kept the original relay for the ecu/fuel pump. You can replace it if you want. The relays under the hood don't attach to the ecu. Make sure you keep the body harness though. Okay I also had a harness made with the ecu it has a cts, 4 Injector wire , 02, iat sensor, crank postion sensor, smart coil wires and tps and that’s it. On the coolent temp sensor(cts) it doesn’t have the wire for the gauge which is prolly the one you mention thats off the stock harness? What I’m questioning is,the body harness which plug into the pop up relays under the hood right? Goes back thru under the dash which in that same harness plugs or goes to all the fuses inside, ac, radio etc but that body harness also plugs into the stock ecu harness. Do I need to have the body harness pluged into the stock ecu/engine harness.Do I need to run the stock harness and ecu for the coolent sending unit to the gauge for it to work? I also have a aftermarket wire/fuse kit for the fuel pump ignition and aftermarket ecu to get it power, may sound lil confusing but I hope you or someone gets what I’m saying the kit tho need to utilize the stock harness for the fuel pump I’ll try and upload the install pdf and sum pics later on to help get a better view on things Quote Link to comment Share on other sites More sharing options...
86technica Posted January 2 Author Report Share Posted January 2 4 hours ago, TSITy said: The technica cluster does not need any signals from the ECU. I can provide you the entire pinout and schematic that I have drawn up, although the colors may be inaccurate as I put it in an 87. It is currently unfinished. I converted my car from analog -> digital gauges and still need to finish the HVAC patch cable that I've been putting off, but the rest of it is finished and confirmed working. When this is done completely, I will be posting the schematics for free for anyone to use (unlike a lot of people who have charged for these things in the past). I can send you the unfinished one if you'd like Yes I might could use that later on would you happen to know about going digital ->analog? My digital cluster is cooked so I wanna try and go to analog for the time being Quote Link to comment Share on other sites More sharing options...
TSITy Posted January 2 Report Share Posted January 2 (edited) 5 hours ago, 86technica said: Yes I might could use that later on would you happen to know about going digital ->analog? My digital cluster is cooked so I wanna try and go to analog for the time being To do digital to analog, you will need a mechanical speedometer cable, an analog fuel sending unit (it has a green connector), and it makes it much easier if you have a parts interior harness so you can splice the stock analog plug end on (I have one if you need it), unless you have a different preferred plug like deutsch, weatherpack, etc. It will be harder to convert back to digital in this case, as the digital dash has plugs right into the cluster, unlike the analog which has a pigtail. But if it doesn't work, you probably don't care. I would buy the parts you have remaining (you will have a leftover digital fuel sending unit (blue plug), and a speed pulse generator that you will have to remove to install the mechanical speedo cable, DO NOT THROW THIS STUFF AWAY!!! I will buy them) and the cooked cluster if you want to do this swap. I like fixing boards. Be aware that it isn't super easy to swap this stuff; it does make it easier if I make the schematics Edited January 2 by TSITy 1 Quote Link to comment Share on other sites More sharing options...
TSITy Posted January 2 Report Share Posted January 2 5 hours ago, 86technica said: Okay I also had a harness made with the ecu it has a cts, 4 Injector wire , 02, iat sensor, crank postion sensor, smart coil wires and tps and that’s it. On the coolent temp sensor(cts) it doesn’t have the wire for the gauge which is prolly the one you mention thats off the stock harness? What I’m questioning is,the body harness which plug into the pop up relays under the hood right? Goes back thru under the dash which in that same harness plugs or goes to all the fuses inside, ac, radio etc but that body harness also plugs into the stock ecu harness. Do I need to have the body harness pluged into the stock ecu/engine harness.Do I need to run the stock harness and ecu for the coolent sending unit to the gauge for it to work? I also have a aftermarket wire/fuse kit for the fuel pump ignition and aftermarket ecu to get it power, may sound lil confusing but I hope you or someone gets what I’m saying the kit tho need to utilize the stock harness for the fuel pump I’ll try and upload the install pdf and sum pics later on to help get a better view on things The stock ECU has a separate wire and sensor from the gauge. You will be able to remove the ECU harness with no issues. Worst case scenario, you can always just run a drop from the gauge cluster out to the temp sensor, then you will know that it is hooked up correctly, but you should not have to do this. Quote Link to comment Share on other sites More sharing options...
86technica Posted January 2 Author Report Share Posted January 2 3 hours ago, TSITy said: To do digital to analog, you will need a mechanical speedometer cable, an analog fuel sending unit (it has a green connector), and it makes it much easier if you have a parts interior harness so you can splice the stock analog plug end on (I have one if you need it), unless you have a different preferred plug like deutsch, weatherpack, etc. It will be harder to convert back to digital in this case, as the digital dash has plugs right into the cluster, unlike the analog which has a pigtail. But if it doesn't work, you probably don't care. I would buy the parts you have remaining (you will have a leftover digital fuel sending unit (blue plug), and a speed pulse generator that you will have to remove to install the mechanical speedo cable, DO NOT THROW THIS STUFF AWAY!!! I will buy them) and the cooked cluster if you want to do this swap. I like fixing boards. Be aware that it isn't super easy to swap this stuff; it does make it easier if I make the schematics Okay that sounds like a lot I have no clue how to do right the first time lol so I’ll prolly just stick with a digital cluster so with that when I get to installing a cluster I’ll see if Steve Sutherland or anyone else has a working one for sell I know they are super rare but it would make life easier. I also did a Manuel swap on this car shout out to kev I would’ve not been able to do it if that forum didn’t exist lol but that harness and speedo cable mainly speedo cable interfere with the digital cluster being it was a 4 speed auto before and having different speedo cables? They might be same I’ll have to look later but just in case. Quote Link to comment Share on other sites More sharing options...
86technica Posted January 2 Author Report Share Posted January 2 3 hours ago, TSITy said: The stock ECU has a separate wire and sensor from the gauge. You will be able to remove the ECU harness with no issues. Worst case scenario, you can always just run a drop from the gauge cluster out to the temp sensor, then you will know that it is hooked up correctly, but you should not have to do this. So as far as gauges go I really could just run aftermarket coolent gauges and what not but I’m still confused cuz the interior harness has a big blue connector on the end that plugs into the stock harness is that important or not? Along with the fuel pump power wire I believe, it’s a red and white wire that goes in a lil box on the stock harness I need that wire to hook up my fuse and wire kit to have power to the pump the kit is “painless” performance cirkit 70113 how would or should I go bout this being I have the aftermarket ecu and harness? I’m stump it’s like I have 2 harness that plug or work with a harness that not being used cuz everything In the engine bay has been changed and replaced or remove like the intake and knock sensor for ex. The new ecu has the knock sensor built in and the intake is mpi you know what I mean Quote Link to comment Share on other sites More sharing options...
tux Posted January 2 Report Share Posted January 2 are you talking about the harness that plugs into the big relay by the ecu? Quote Link to comment Share on other sites More sharing options...
psu_Crash Posted January 4 Report Share Posted January 4 The factory coolant temp gauge comes right from the sensor. The other temp sensor goes to the ECU. Sounds like you just have that unplugged. I'm not sure what color the connectors are. I assume you have downloaded the factory schematics? The connectors all have names there. The ECU you have should be setup to control the stock fuel pump relay. OR are you attempting to bypass that relay with the painless kit? The new ECU may have input for a knock sensor, but you would still utilize the factory (or aftermarket) knock sensor. That connects to the knock box to pull timing when knock it detected. I don't believe it connected to the factory ECU at all. I'm a little confused where your problem lies, but it's early, I'm still on coffee #1. Quote Link to comment Share on other sites More sharing options...
86technica Posted January 5 Author Report Share Posted January 5 14 hours ago, psu_Crash said: The factory coolant temp gauge comes right from the sensor. The other temp sensor goes to the ECU. Sounds like you just have that unplugged. I'm not sure what color the connectors are. I assume you have downloaded the factory schematics? The connectors all have names there. The ECU you have should be setup to control the stock fuel pump relay. OR are you attempting to bypass that relay with the painless kit? The new ECU may have input for a knock sensor, but you would still utilize the factory (or aftermarket) knock sensor. That connects to the knock box to pull timing when knock it detected. I don't believe it connected to the factory ECU at all. I'm a little confused where your problem lies, but it's early, I'm still on coffee #1. Quote Link to comment Share on other sites More sharing options...
86technica Posted January 5 Author Report Share Posted January 5 Tmmr I am going to try to upload sum pictures or links of the stock ecu and the part of the Instructions that explain how to install the cirkit I think it will help with what I’m trying to say but yes the new ecu has control of the fuel I might be trying to bypass the the relay but I’m not sure wiring is not my thing lol. When I got the ecu I asked motocam360 about the knock sensors and if I would need to still have and they said no and that its built into the ecu Quote Link to comment Share on other sites More sharing options...
psu_Crash Posted January 8 Report Share Posted January 8 On 1/5/2025 at 12:27 AM, 86technica said: Tmmr I am going to try to upload sum pictures or links of the stock ecu and the part of the Instructions that explain how to install the cirkit I think it will help with what I’m trying to say but yes the new ecu has control of the fuel I might be trying to bypass the the relay but I’m not sure wiring is not my thing lol. When I got the ecu I asked motocam360 about the knock sensors and if I would need to still have and they said no and that its built into the ecu Interesting. I'll have to read through that Quote Link to comment Share on other sites More sharing options...
86technica Posted January 9 Author Report Share Posted January 9 16 hours ago, psu_Crash said: Interesting. I'll have to read through that Hey I’ve uploaded sum pics on the member gallery cuz I don’t know how to upload to this forum every pic was about 232kbs so hopefully it’s seen Quote Link to comment Share on other sites More sharing options...
psu_Crash Posted January 11 Report Share Posted January 11 I see the pics you uploaded. I'll try to take a look in the morning over a coffee or 2. Quote Link to comment Share on other sites More sharing options...
ssblast20 Posted January 29 Report Share Posted January 29 On 1/9/2025 at 11:02 AM, 86technica said: Hey I’ve uploaded sum pics on the member gallery cuz I don’t know how to upload to this forum every pic was about 232kbs so hopefully it’s seen Hey, this is Steve, I do have a perfect working digital cluster, and I’m about to possibly part out a full technica car as well. Holler if I can help - Quote Link to comment Share on other sites More sharing options...
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