Rev limiter coming on too early?

Discussions concerning the M7790 cpu

Moderator: Matt

lynchfourtwenty
 

Posts: 108
Joined: Sun Feb 14, 2010 10:02 am

Rev limiter coming on too early?

Post by lynchfourtwenty »

Been a while since I played with my nistune but I have a n/a ve again so I dusted it off..

Problem I'm having is my rev limiter is coming on too early.. example: I had it set to 7500 (factory rev cut) but it was coming on at like 7100~ so I bumped it to 7800 but then it's coming on at 7200~ so I set it to 8050 but it's still coming on at like 7400~

This is according to my nistune logs.. as usual my factory tach isn't very accurate up that high..

Iirc nistune will only rev limit to like 8012rpm.. i read somewhere that issue was fixed? Back when I was using my nistune about 5-6 years ago if I set the rev limiter past 8012 it just wouldn't come on..

Setup is b13 sentra se-r, sr20ve, type 3 board, 64y00 ecu

Hopefully someone has an idea on what's going on.. thanks!
Matt
Site Admin
 

Posts: 8961
Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
Contact:

Re: Rev limiter coming on too early?

Post by Matt »

Can you post a log file and tune file where you have it set highest? I will try it here

The SR20DE ECUs will not do a RPM limit if set above 8012rpm. I have not done a code workaround for it but something I can look into the new year once I get through a few more software updates
lynchfourtwenty
 

Posts: 108
Joined: Sun Feb 14, 2010 10:02 am

Re: Rev limiter coming on too early?

Post by lynchfourtwenty »

it could be my rpm switch cutting out an the cams turning off an on maybe but i dont think so.. plus id hear it lol.. its pretty consistent and feels like the rev limiter..

heres the most recent log / tune
NIStune_33.csv
(18.73 KiB) Downloaded 131 times
starla1.bin
(32 KiB) Downloaded 131 times
thanks
lynchfourtwenty
 

Posts: 108
Joined: Sun Feb 14, 2010 10:02 am

Re: Rev limiter coming on too early?

Post by lynchfourtwenty »

oh an u can see the afr go lean an back as if the injectors were cutting..

this is a pretty old board ive had for atleast 8 years almost lol, idk if its a software/firmware issue? i been reading tryin to catch up lol
Matt
Site Admin
 

Posts: 8961
Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
Contact:

Re: Rev limiter coming on too early?

Post by Matt »

It wont be a firmware issue (original firmware only allowed retuning the standard ECU code). Thanks I'll check the logs out
lynchfourtwenty
 

Posts: 108
Joined: Sun Feb 14, 2010 10:02 am

Re: Rev limiter coming on too early?

Post by lynchfourtwenty »

Cool, thanks!
lynchfourtwenty
 

Posts: 108
Joined: Sun Feb 14, 2010 10:02 am

Re: Rev limiter coming on too early?

Post by lynchfourtwenty »

Did you ever get a chance to look at my log?
Matt
Site Admin
 

Posts: 8961
Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
Contact:

Re: Rev limiter coming on too early?

Post by Matt »

Sorry was on holidays that week. Just looking at log now. Also been looking at the 8012rpm limiter over the last week, taking much longer than I originally expected...

Your TP max table is too low and limiting your injection
64 66 68 70 72 74 80 84 88 96 112 128 128 128 128 128

Try increasing the top numbers (from 88 upwards to 255) to see if this fixes things. It explains why your TP is not increasing further and it is leaning out
Matt
Site Admin
 

Posts: 8961
Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
Contact:

Re: Rev limiter coming on too early?

Post by Matt »

When you hit a rev cut the TP will actually drop to 0 and the injection time will drop, this is not a rev cut in this case
lynchfourtwenty
 

Posts: 108
Joined: Sun Feb 14, 2010 10:02 am

Re: Rev limiter coming on too early?

Post by lynchfourtwenty »

Gotcha.. I'll giver a try an report back
Matt
Site Admin
 

Posts: 8961
Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
Contact:

Re: Rev limiter coming on too early?

Post by Matt »

Three weeks of work later, I've managed to figure out why rpm is limited to 8012. Updated on various ECUs
viewtopic.php?f=12&t=2874&start=120#p26048
lynchfourtwenty
 

Posts: 108
Joined: Sun Feb 14, 2010 10:02 am

Re: Rev limiter coming on too early?

Post by lynchfourtwenty »

Wewt! I'll give it a try this weekend :)
Matt
Site Admin
 

Posts: 8961
Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
Contact:

Re: Rev limiter coming on too early?

Post by Matt »

You got a programmer to reflash the board with the new ENT file?
lynchfourtwenty
 

Posts: 108
Joined: Sun Feb 14, 2010 10:02 am

Re: Rev limiter coming on too early?

Post by lynchfourtwenty »

Lol.. no.. dammit.. :(
Matt
Site Admin
 

Posts: 8961
Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
Contact:

Re: Rev limiter coming on too early?

Post by Matt »

Only way to change the code is to remove the board and reflash. AVP in the states can reflash boards
Post Reply