Sr AIV removal, question for ecu tuners. Quite technical. - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

sr240mike · 11-05-2004, 10:58 PM

Ok so with 300zx's when you install an aftermarket ecu such as JWT the AIV's are deleted in the code somehow and smog is unnaffected. Do they lean out the idle portions of the fuel maps or is there actual code to remove the AIV? After some searching on www.twinturbo.net removing the aiv's without an ecu upgrade it is common for the car to stall while decelerating as well as running fairly rich around idle. That sounds like a similar problem many sr swapped cars have. So if anyone has any insight to this please let me know so I can alter the ecu to adjust for aiv removal. Thanks in advance.

RBS14 · 11-05-2004, 11:24 PM

yes, on some cars JWT does exactly as you said. They lean out the idle to reduce emissions. This is why some newer cars didn't have an AIV, when some older ones did. The engineers just leaned out the idle to be able to do away with the AIV/PAIRC system.

to do it yourself, you'd have to get a new writable eprom and an emulator and whatnot.

sr240mike · 11-06-2004, 01:37 AM

No emulators available yet, but I have a daughterboard and eprom programmer. I was just looking the the stock maps and jwt's of a 300zx tt and dont see any differences in the closed loop maps. Yeah 93 and newer 300zx's didnt have the aiv's, do blacktop sr20's have them?

RBS14 · 11-07-2004, 01:35 PM

what do you mean, no emulators available yet, there are a few different ones. Maybe it couldn't emulate the eproms that SR's use? I know people have used them on KA eproms. There was a link on some ecu tuning forum I used to visit. Problem with SR's is that they have dual eproms or something like that, which is incredibly difficult to figure out. I'm not sure if blacktop SR's have AIV's or not.

sr240mike · 11-08-2004, 08:29 PM

Sr's daughterboards are 16 bit so you would need 2 emulators but some people are working on it.

11-05-2004, 10:58 PM	#1
sr240mike Zilvia FREAK! Join Date: Apr 2004 Location: California, Norcal biiaatch Posts: 1,185 Trader Rating: (0) Feedback Score: 0 reviews	Sr AIV removal, question for ecu tuners. Quite technical. Ok so with 300zx's when you install an aftermarket ecu such as JWT the AIV's are deleted in the code somehow and smog is unnaffected. Do they lean out the idle portions of the fuel maps or is there actual code to remove the AIV? After some searching on www.twinturbo.net removing the aiv's without an ecu upgrade it is common for the car to stall while decelerating as well as running fairly rich around idle. That sounds like a similar problem many sr swapped cars have. So if anyone has any insight to this please let me know so I can alter the ecu to adjust for aiv removal. Thanks in advance. __________________ TWO IN THE COOT, ONE IN THE POOT

11-05-2004, 11:24 PM	#2
RBS14 Nissanaholic! Join Date: Feb 2003 Location: Santa Cruz/San Diego Posts: 2,271 Trader Rating: (0) Feedback Score: 0 reviews	yes, on some cars JWT does exactly as you said. They lean out the idle to reduce emissions. This is why some newer cars didn't have an AIV, when some older ones did. The engineers just leaned out the idle to be able to do away with the AIV/PAIRC system. to do it yourself, you'd have to get a new writable eprom and an emulator and whatnot. __________________

11-06-2004, 01:37 AM	#3
sr240mike Zilvia FREAK! Join Date: Apr 2004 Location: California, Norcal biiaatch Posts: 1,185 Trader Rating: (0) Feedback Score: 0 reviews	No emulators available yet, but I have a daughterboard and eprom programmer. I was just looking the the stock maps and jwt's of a 300zx tt and dont see any differences in the closed loop maps. Yeah 93 and newer 300zx's didnt have the aiv's, do blacktop sr20's have them? __________________ TWO IN THE COOT, ONE IN THE POOT

11-07-2004, 01:35 PM	#4
RBS14 Nissanaholic! Join Date: Feb 2003 Location: Santa Cruz/San Diego Posts: 2,271 Trader Rating: (0) Feedback Score: 0 reviews	what do you mean, no emulators available yet, there are a few different ones. Maybe it couldn't emulate the eproms that SR's use? I know people have used them on KA eproms. There was a link on some ecu tuning forum I used to visit. Problem with SR's is that they have dual eproms or something like that, which is incredibly difficult to figure out. I'm not sure if blacktop SR's have AIV's or not. __________________

11-08-2004, 08:29 PM	#5
sr240mike Zilvia FREAK! Join Date: Apr 2004 Location: California, Norcal biiaatch Posts: 1,185 Trader Rating: (0) Feedback Score: 0 reviews	Sr's daughterboards are 16 bit so you would need 2 emulators but some people are working on it. __________________ TWO IN THE COOT, ONE IN THE POOT