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Hey all,

I was wondering if anyone would be able to help me out, I have installed bigger injectors over my stock injectors because most of them were leaking in some form or another into my 93 r32 Gtr, this part was fairly easy.

I have installed a nistune ecu into my car as well and intended on just using the 'resize injectors' operation, I did this and initially left all 3 adjust options ticked and then simply uploaded and burned to the eprom.

The car then wouldnt start firing. I have only just began using nistune and the software and I was wondering if have done something wrong, if I am only changing the injector size do I tick those 'adjust' options or untick them?

I did restore the ecu to the default rom that comes with nistune and it started firing, so my adjustment be wrong with the resizing operation.

Anyone know how to fix this or the procedure to resize injectors for a r32 gtr?

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Here try this, may help. NIStune_Mapping_Guide.pdf

Depends on what size the injectors are as the engine may still run (albeit badly) if the difference in size of your new ones aren't that much bigger than your stock 444s

Did you also remember to adjust the latency? It makes a big difference at idle.

This is the note from my DIY

"- If using Nistune; turn the ignition on, load the config from the ECU, save a copy of the config to disk. Select 'Operations -> Resize Injectors'. Enter the original injector size and the new injector size. If the current injectors are OEM you can pull the size in with the 'Factory CC' button. If the new injectors have a different latency to the old ones, use 'Injector Latency -> Change Constant' to make the correction. Apply the new config to the ECU and save the new config to disk using a different filename."

I think it has been said by afew people they have got ID1000's to idle nicely with Nistune, maybe ID2000's also but I'm not 100% sure on that. As for AFMs, Nistune has a bunch of them preset which can be selected from a dropdown box, would need the software to know exactly which are preset, otherwise I think you can program an unknown one in knowing the voltage corrections.

Thanks for all the information, the mapping guide helped a bit but MrStabby pointed out the main problem, I didnt realise the new injectors had a latency of 850us, cant believe 80us makes such a difference, it now runs very well again and yay no more leaking injectors, hopefully now ill get decent fuel economy

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