Jump to content
SAU Community

Recommended Posts

  • 4 weeks later...

R33 ECU can't be reprogrammed, only R32 can. Best of luck trying it unless u get a replacement chip something like a Powerchip?

PowerFC works only with manual cars, not with auto so auto GTS-t owners are left stranded out there. So if they got an auto, then RSM for $300-400 or speed cut removing device like HKS/Trust SCD around $85 or cut wire 53 for free with risk it may affect something else....

Link to comment
https://www.sau.com.au/forums/topic/44988-speed-limiter/#findComment-959676
Share on other sites

Has anyone actually looked at a wiring diagram for where this wire 53 goes?  I have heard all this talk about it not being good for HICAS but does it actually go to the HICAS computer?
According to the wiring diagram, wire #53 is a branch off the connection to the HICAS unit. The ECU does not become part of the circuit controlling HICAS. That would explain why, in general, the HICAS is not affected when #53 is cut.
Link to comment
https://www.sau.com.au/forums/topic/44988-speed-limiter/#findComment-960047
Share on other sites

According to the wiring diagram, wire #53 is a branch off the connection to the HICAS unit. The ECU does not become part of the circuit controlling HICAS. That would explain why, in general, the HICAS is not affected when #53 is cut.

Ok, now does the ECU requires speed signal in conjunction with other factors such as engine rpm, throttle pos, crank angle, etc to determine how much fuel to add into the engine? Will cutting this "magical" wire 53 to make the ECU "speed blind" will have effect on any A/F ratio or timing or anything else?

Link to comment
https://www.sau.com.au/forums/topic/44988-speed-limiter/#findComment-961001
Share on other sites

Ok, now does the ECU requires speed signal in conjunction with other factors such as engine rpm, throttle pos, crank angle, etc to determine how much fuel to add into the engine? Will cutting this "magical" wire 53 to make the ECU "speed blind" will have effect on any A/F ratio or timing or anything else?

Thats exacly what i was thinking, How about putting a switch there so u can choose when to have the limited off for the track etc

Link to comment
https://www.sau.com.au/forums/topic/44988-speed-limiter/#findComment-961069
Share on other sites

wire 53 is used by hicas diagnostic and ecu to monitor speed in km/h. mine has the speed cut take off (unsure how) and i have no running problems etc.. i dont believe cutting 53 causes any problems other than being unable to exit hicas diagnostics once you enter it. it wont break hicas or make it stop working its just if you do hicas diag mode you cant exit it easily

so ive read anyway

Link to comment
https://www.sau.com.au/forums/topic/44988-speed-limiter/#findComment-962111
Share on other sites

AFAIK, the speed signal has no effect on fuelling, it is simply telling the ECU how fast the car is travelling. When the ECU detects that the car is up to a predetermined speed, it starts into a section of its programming to limit the speed by cutting fuel and / or spark.

Link to comment
https://www.sau.com.au/forums/topic/44988-speed-limiter/#findComment-962134
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Given by the sheer number of questions about offset, absolutely not. If you had the information formatted this way: Space from R34 GTT hub to outer arch = 100mm Space from R34 GTT inner hub to nearest suspension arm = 90mm. (making this up) Buying a wheel that was advertised as Enkei RPZ5 Diameter 18in Width 9 Distance to arch = 84mm Distance to suspension arm = 76mm 100% of people would know instantly if it fits. They would absolutely also know instantly how close it fits too, and no questions would need to be asked. You would know you would have 16mm from the guard and 14mm from the suspension arm.
    • Ah ok, for example for the apexi ecu I heard that it's pretty limited with the information it can give you. Also not sure why Nissan used the consult port over the obd2, what the idea there was.
    • Diagnosing with and without is mostly the same. You need to know, as Duncan asked, and what conditions. Car hot, cold, idling, driving, if while driving what rpms, is when you're varying, or is it when held constant.   From there it's understanding what can be causing it. Starting with pretending all of the sensors are correct. Which means if it's going rich, why would it be thinking more air is going in than it is, and under what conditions. So things like if only when under boost, it could be be a loose intake piping joint. It's just understanding the system, and understanding when/how the problem occurs, and then if it's only occuring in specific scenarios, what can be causing it.   ECU specifically, if it's aftermarket, it'll have software you can use, for the Skylines on factory ECU, there is Nissan Consult you can use. Most ECUs have a way to get data from them.
    • How do you go about diagnosing ecu's that don't have data logging, is it more experience at that point and just trying out things that you think will fix the issue?
    • Stock O2 are basically useless beyond anything at stoich. Any misfire will also be seen as lean. The stock O2 also read a collective exhaust gas volume, not each cylinder. Sputtering and missing means not each cycle is firing, and some are. Which means even if rich, as shit, on cylinders as they miss, they'll read lean, but the cylinders that did fire will read rich, and combined, well, they can read anything from rich to lean.   Start with the basics before even going looking at sensor values.   Edit: I say the above, and that's coming from the guy with a few thousand dollars worth of scan tools sitting right beside me right now that I use frequently for my job.
×
×
  • Create New...