smason Posted April 15, 2020 Report Share Posted April 15, 2020 Hi All, I recently picked up a Link G4+ Xtreme + Full Harness, And ive got some questions. Car is a 89 240sx with Non vvti 1JZGTE + R154 For the O2 sensor, I have a glowshift wideband that has a 0-1v analog output that I use for the factory 4 row ECU. Is this okay to run to the G4? I would like my Speedo and Tacho to work. I understand the G4 can do a tach output, What about speed? I think i am missing the r154 VSS but i could get one if thats required. Aside from changing the Supra base map trigger to 355, is there anything else I need to do to the MAP? I plan on driving the car to a tuning shop down the road. Im very hopeful this fixes my issues. This engine has been significantly down on power and misfires at low RPM with the factrory ecu. Thanks! Quote Link to comment Share on other sites More sharing options...
Adamw Posted April 15, 2020 Report Share Posted April 15, 2020 1 hour ago, smason said: For the O2 sensor, I have a glowshift wideband that has a 0-1v analog output that I use for the factory 4 row ECU. Is this okay to run to the G4? The 0-1V signal is usually a simulated narrowband signal. Im pretty sure they have a 0-5V wideband output wire as well which would be the better option. 1 hour ago, smason said: I would like my Speedo and Tacho to work. I understand the G4 can do a tach output, What about speed? I think i am missing the r154 VSS but i could get one if thats required. The ECU can do a calibrated speedo output. You will need a speed input from a VSS. The output to the speedo will need a small circuit to make it compatible with the nissan speedo which expects an AC signal. 1 hour ago, smason said: Aside from changing the Supra base map trigger to 355, is there anything else I need to do to the MAP? I plan on driving the car to a tuning shop down the road. You will need to assign all the inputs and outputs to match your wiring. Apart from those and the trigger offset you will likely also need to adjust the master fuel number to get it to run decent also. smason 1 Quote Link to comment Share on other sites More sharing options...
smason Posted April 16, 2020 Author Report Share Posted April 16, 2020 Looks like there is 3 wires. Ill be sure to use the 0-5v. Thanks! For the 1uF cap, is there a voltage rating i should be looking at? I found a 12v off Digikey that should work. Thanks for the info in such a timely manner! Quote Link to comment Share on other sites More sharing options...
Adamw Posted April 16, 2020 Report Share Posted April 16, 2020 Yes that cap will be fine. Any ceramic or tantalum (maybe easier to find in 1uF), 20/30/50V will do it. smason 1 Quote Link to comment Share on other sites More sharing options...
smason Posted April 17, 2020 Author Report Share Posted April 17, 2020 Cap ordered, For the R154 VSS, would my best option be the Marlin Crawler VSS unit, or could i use the existing sensor? Quote Link to comment Share on other sites More sharing options...
JMP Posted April 17, 2020 Report Share Posted April 17, 2020 R154 VSS interfaces just fine to the link Quote Link to comment Share on other sites More sharing options...
smason Posted April 18, 2020 Author Report Share Posted April 18, 2020 18 hours ago, JMP said: R154 VSS interfaces just fine to the link Could you be so kind as to clarify, do you mean the factory ABS sensor? I heard something about it hitting a 500Hz limit Quote Link to comment Share on other sites More sharing options...
JMP Posted April 18, 2020 Report Share Posted April 18, 2020 not the ABS sensor, the speed sender, wire it like this: Quote Link to comment Share on other sites More sharing options...
smason Posted April 22, 2020 Author Report Share Posted April 22, 2020 Perfect, I was missing the screw on part which is why I couldn't ID it. Ordered. I've connected the Chase Bays harness and it seems to not be as "plug and play" as I'd hoped. It looks like I am getting constant power to my coils. I figure this should be on switched power instead. The blue light always stays on. Should this not be the case? Or is there a programmable input for the switched power? Thanks Quote Link to comment Share on other sites More sharing options...
Adamw Posted April 23, 2020 Report Share Posted April 23, 2020 I dont expect constant power at the coils would cause the ecu to stay on as the ignition drives cant backfeed, so it sounds like there is a problem somewhere else. Since it is a stepper motor engine there should be an ecu hold power aux output wired to control the main relay. You will really need to get a wiring diagram from the chase guy to know what they have done. Quote Link to comment Share on other sites More sharing options...
smason Posted April 25, 2020 Author Report Share Posted April 25, 2020 Just thought I'd update, there seems to be an issue with the ign driver as pin A10 is outputting 5v constantly. Not sure why, although it still manages to fire the coil. Car is running, now to button things up.. Quote Link to comment Share on other sites More sharing options...
smason Posted April 26, 2020 Author Report Share Posted April 26, 2020 Okay so Ive found a few more issues around the creature comforts. Speed and Tacho. The car runs and now waiting for some dyno time. Ive created the cap/resistor circuit for speedo output, and wired the tacho to Aux 6 and 5 respectively. Ive tried to turn this on and it seems not to work. Ive got key sweep on and i dont get anything on the dash. The car is a S13 240sx. I believe this is user error and would like some guidance. Ive set the Auxilary outputs, yet when looking at runtime values, they show as off. Any ideas? Not sure about sweep freq yet.. Quote Link to comment Share on other sites More sharing options...
Adamw Posted April 26, 2020 Report Share Posted April 26, 2020 1 hour ago, smason said: Ive set the Auxilary outputs, yet when looking at runtime values, they show as off. Any ideas? The runtimes will show off when set up to a pulsed output. The "active" runtime only works for basic on/off type functions like fuel pumps/fans etc. Your Aux set-up looks correct for the tacho. For the speedo, set offset to zero, max freq to 500 and sweep freq to 500, sweep time to 2s and hopefully you will see some movement next key-on. Im not very familiar with the american 240SX, what did they have for an ignition system originally? Distributor and single coil or multi coil? Quote Link to comment Share on other sites More sharing options...
smason Posted April 26, 2020 Author Report Share Posted April 26, 2020 Mine was a 1989 with KA24E and it was a single coil (igniter) and distributor iirc. Trying the speedo settings now. Quote Link to comment Share on other sites More sharing options...
smason Posted April 26, 2020 Author Report Share Posted April 26, 2020 No dice on either. It seems as though there is an issue with the cluster maybe. Is there any way i can be sure the ecu is outputting the signal? Voltage or resistance? In other news, I drove the car on the base tune for the first time. Wow. That was way faster than the car ever was on the stock ecu. Like crazy. I just wish the gauges worked now. Side Note. My oil pressure was 6psi lower than normal. Has anyone seen this? Additionally, What would the Key sweep occur on? Ignition power? or Start signal? I have my Ignition input on low activation because the entire harness is on switched power. The DI i have is for start signal. Quote Link to comment Share on other sites More sharing options...
Vaughan Posted April 26, 2020 Report Share Posted April 26, 2020 If it is a distributor car from factory the tacho most likely needs modification to work with an ecu signal instead of a coil signal. I've modified an mr2 tacho before with a couple of resistors, not sure how to do your one but some people have managed to trigger coil controlled tacho's by wiring a relay coil up to simulate the coil signal. I believe the sweeps happen when the ecu powers up. Quote Link to comment Share on other sites More sharing options...
Adamw Posted April 27, 2020 Report Share Posted April 27, 2020 15 hours ago, smason said: It seems as though there is an issue with the cluster maybe. Is there any way i can be sure the ecu is outputting the signal? Voltage or resistance? You can check the output with an LED testlight, connect between the aux and ground, it will flash from slow to fast then back to slow during the key on sweep. The tacho could potentially be a high level type as Vaughan suggests, I know some of the basic SR20 distributor nissans such as primeras etc had a high level tacho but didnt expect it in a S13. Quote Link to comment Share on other sites More sharing options...
smason Posted April 27, 2020 Author Report Share Posted April 27, 2020 Hm. Ill test that shortly. Neither speedo or tacho are working. I think my VSS might be bad, is there a way to simulate an output to check my speedometer? The cap/resistor circuit makes a sin wave across 0v, so if i send a DC voltage it should work, no? Found this: He was trying to get his cruise working. Quote Link to comment Share on other sites More sharing options...
Adamw Posted April 27, 2020 Report Share Posted April 27, 2020 The sweep will work regardless of whether the VSS working or not. A different test you can do to test the speedo is you can just set that aux output to "Test PWM" mode and try different frequencies, anything from 50-500Hz I should do something. Quote Link to comment Share on other sites More sharing options...
smason Posted April 29, 2020 Author Report Share Posted April 29, 2020 So after lots of research, it appears that there is a difference internally from the SOHC to DOHC versions of the car, mine is an 89 with single slammer, I swapped the dash over to a DOHC, and it seems to be functional. Whether that was my specific unit or a actual incompatibility I am not sure. Now to tune the multiplier. And the tach jumps around alot. Not very smooth. Any advice? Quote Link to comment Share on other sites More sharing options...
Adamw Posted April 29, 2020 Report Share Posted April 29, 2020 Multiplier would normally be 1.0 for a tach (1 pulse per spark). Not sure why the tach would be bouncing, you could try adjusting the duty cycle a bit either way - normally 50% but you could see if 30 or 70 made it any better. Quote Link to comment Share on other sites More sharing options...
smason Posted April 29, 2020 Author Report Share Posted April 29, 2020 Spoke too soon. Something is still wrong. Speedo does not work and tach is stuck at 7k. Im using aux 5 and 6. Is there any issues with that? Quote Link to comment Share on other sites More sharing options...
smason Posted April 29, 2020 Author Report Share Posted April 29, 2020 I was checking run time values and i see this. Does this have something to do with it? Quote Link to comment Share on other sites More sharing options...
smason Posted April 29, 2020 Author Report Share Posted April 29, 2020 Found this: "The dohc tach and sohc tach work completely different. The sohc works on a pulse single just like an autometer tach. the dohc tach works on a voltage scale." Quote Link to comment Share on other sites More sharing options...
smason Posted April 29, 2020 Author Report Share Posted April 29, 2020 Im just compiling all the info i can find online here. Sorry for the spam. The DOHC tach gets a 0-5V signal from the ECU and the SOHC tach gets a 0-12V signal off the coil. Quote Link to comment Share on other sites More sharing options...
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