Jump to content
SAU Community

GTR engine problem

dairyboy

By dairyboy,
in Engines & Forced Induction

 Share

Recommended Posts

dairyboy Collaborator

dairyboy

Posted
  • Author
Posted

Another problem just come to mind - been reading the ECu resetting threads and it seems like my ECU should be reset already. My car battery doesn't hold any charge whatsoever and is usually left there for 2 or more days. Do I still need to short certain wires of the wiring loom just to turn it into diagnostic mode then let it reset itself that way?

Link to comment
Share on other sites
blind_elk Grand Master

blind_elk

Posted
Posted
when the car is turned on why would the battery affect anything? as the alternator is supplying enough voltage for everything so how could the ecu 'sense poor voltage'??
Not only is the alternator supplying volts to run everything, it is supplying volts to recharge the battery. And with a dead battery, it is supplying HEAPS of volts to try and recharge the battery. The ECU can sense this, and reckons its not a good thing.

A new battery could well solve the problem. And changing the battery will effectively cause a ECU reset.

Link to comment
Share on other sites
bangin Enthusiast

bangin

Posted
Posted
Ok...

Parts needed - plugs, battery and possiby O2 sensor and inlet gasket

Need to look at - plugs, inlet gasket and O2 sensor

Anything else to that list? Troubleshooting this mofo makes me pull all my hair out

just reading other peoples responses and they are all possible solutions so heres mine. check afm you said it had a z32 unit and now the stock units. check afm connection. the stock afm's may be faulty and if the stock ecu senses this it runs in limp mode and that maybe your reasons for hard to start and bad idling. i think when the ecu senses the fault in the afm it will not allow the motor to rev very high. just a thought. good luck

Link to comment
Share on other sites
Whoneedstherapy Veteran

Whoneedstherapy

Posted
Posted

Just a quick thought here.

Was it running a standard ecu with the z32's when you got it?? IF so when you changed the AFM's to standard im guessing you didn't have the computer remapped to suit the standard afm's??

This could be one part of your problem now as if you had a standard ecu with z32 afm's your ecu has definately been remapped, which isn't really a bad thing, but in changing to a standard air flow meter the ecu is going to be getting incorrect signals from the standard airflow meter.

IF i was you i'd take it to a good workshop, sit down and talk to them about it, put all the gear it came out with back on and see how you go.

Link to comment
Share on other sites
blind_elk Grand Master

blind_elk

Posted
Posted
Ok...

Parts needed - plugs, battery and possiby O2 sensor and inlet gasket

Need to look at - plugs, inlet gasket and O2 sensor

Anything else to that list? Troubleshooting this mofo makes me pull all my hair out

A BLOODY BATTERY!!!!!!!!!!! :D

Link to comment
Share on other sites
Rowdyr32 Mentor

Rowdyr32

Posted
Posted

Try pulling the plugs off each injector one at a time whilest the engines running. Could possibly give you an indication if its an injector. Also could it be the valve clearances? Have you done a compression check on the engine yet? Have you checked the fault codes on the ecu? The 26 I just put in my car ran like a pig and idled rough because I wired up the knock sensors around the wrong way. Good luck man!

Link to comment
Share on other sites
  • 10 months later...

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
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • 70RTY
      JDM R35 Bought at Japanese Auction

      By 70RTY · Posted

      Hi all,   I have been a member here for years and am back to owning an R35.  It's my car and thought members of the community might enjoy sharing my journey.  I am definitely here to join the conversation.  If sharing this content isn't appropriate or it belongs somewhere else, I am happy to have it deleted or moved...
    • Dose Pipe Sutututu
      R34 GTT RB rough idle problem with weird RPM gauge fluctuations

      By Dose Pipe Sutututu · Posted

      Data looks rock solid? I'm assuming you jabbed the throttle twice OR once? the TPS voltage moves up and down twice, however you've mentioned you did it once.
    • luke gtr
      JDM R35 Bought at Japanese Auction

      By luke gtr · Posted

      Having not watched the videos, I'm unsure, but this may be better suited to the importing thread?
    • Joni Boi
      R34 GTT RB rough idle problem with weird RPM gauge fluctuations

      By Joni Boi · Posted

      Update on this situation: (Forgot to put in my previous post that I bought another brand new pressure gauge and fuel shows the same 50psi) I've deleted all the aftermarket immobilizers and turbo timer shyt and placed all factory wiring back to normal. The problem is still the same and nothing changed, but atleast it's a bit more tidier under the steering wheel. I've also siphoned out all the old fuel and then poured new batch of BP98 fuel (about 15L) into the tank. Nothing changed. Still the same idle. I also changed out the MAP vac line with a new one and, still the same.  So 2 days ago, I thought fk it. I'll just change out the fuel rail and injectors with another set that I know worked well in my brother's R34 a while back. That other fuel rail has the exact same Xspurt 640cc as what I have right now. So I changed it out to that other fuel rail and injectors (new O-rings) and injector harness. Put everything back together, started the engine, 464906286_1624569924763105_5179888796065901094_n.mp4   and yeah... still the same 50psi and idle problem. 🫠 I can also hear each of injector's solenoids running when I put a screw driver to it and have the other end to my ear. I might get a noid light just to confirm pulsasion but yeah, very strange that both fuel rails and injectors put out 50psi.  31-10-2024.csv I've attached it here. I started recording, then started the engine and let it idle with no throttle, then at the end I applied a little throttle and then stopped recording.    So, now idk. I'm going to see if swapping out the brand new R35 coils to my old splits fires will change anything. 🤷‍♂️
    • PranK
      JDM R35 Bought at Japanese Auction

      By PranK · Posted

      Hey mate, nice work on the car. Just a quick note, people generally don't like it when you use the forums to dump and run to advertise your YouTube content. If you're gonna stick around and join in the conversation then great, but if not this might not be the best place for you.  
×
×
  • Create New...