auto ecu same as 5-speed ecu

[cf1203]

Does anybody know if an auto ecu is the same as a 5-speed ecu? If they arent the same, what is the difference?

[navysnail]

nope, auto tells transmission when to shift, some sensors like the tps have different imputs to the ecu, for instance, if the tps regesters more than x% throttle, then it will downshift. also auto doesnt have speed cut.

[Dorifto Sil80]

Do you know how to reset the ECU, so that the Rev Limiter will not kick in at 5k RPM on a manual, when actual redline is about 6.5-7k ?

[niznos]

Dorifto Sil80, My 1990 doesn't cut at 5000 RPMs, you may have a problem with yours. Unless you are talking about the top speed limiter, then the only way to get rid of that is to get a remapped ECU or get an ECU from an auto trans 240 89-90 model years. I've got that and I get to go faster than 119 now.

http://www.nissaninfiniticlub....69066Talk to this guy, see if he's talking about a 240, then get his ECU to rid yourself of the limiter.

[navysnail]

you can also cut a wire that tells the ecu how fast your going

[niznos]

I've investigated all the rumors about the cut wire, and it has drawbacks like no speedo, or cruise, some even report ECU going into safe mode. The auto ECU has no drawbacks, I've ran it for a month now.

[ZULU]

Niznoz isnt it true that swapping your 5 speed ECU for a auto ecu removes the rev limiter as well ? I have heard this numerous times but wanted to double check with someone that acutally did the swap.

[cf1203]

well if any of you want to find out, I have an auto ecu i will sell from a 95 240sx. If you want it, make me an offer.

[niznos]

ZULU, I do not know this for sure. Since there is not much to be gained to go past 6000RPMs, I haven't rev'd it that high. I personally don't see any more HP to be had up there, even with my R4 cam. I have never had it on a dyno, so I can't say for sure if there isn't any HP there, but I feel pull drop off up there.

This is on the SOHC engine, so I don't know specifics on your 95. If you are wanting to do this, better make sure it applies to the DOHC's too.

[Dorifto Sil80]

niznos, Yeah, my rev limiter kicks in at around 5100 RPMs, this is in atleast 1st and 2nd. I haven't gone over 80mph in my 240 yet, so I'm not sure if it limits 4th and 5th. Someone told me that if I just unhook my battery for about an hour, then re-connect it, that the ECU and everything else in the car will be reset..i.e-radio station presets, clocks, etc. I'll probably try that first, if it doesn't work, I'll either live with 5100 RPM redline, or try out the auto ECU. Thanks!

[niznos]

You know what that sounds like? Our transmissions have sensors so that the ECU knows when you are in 3rd, 4th, and 5th gears. Once you are in 4th or 5th, the rev limit is dropped so that you do not surpass the 119mph programmed speed limiter (our speed limiter is actually a dropped rev limit at certain gears). It may be that you have a 4th and/or 5th gear sensor stuck on. Since the ECU thinks you are in 4th or 5th all the time, it will initiate the lower rev limit to keep you below 119. If I remember correctly, those sensors are on the passenger side with a two wire harness connected to them. My old sensors started to leak gear oil through them, so I had to replace them at around $26ea. You may want to remove and meter them for open/closed circuits as you push in on the switch. You will loose some gear oil when you take them out, so have some handy.

[niznos]

There is a guy selling an auto ECU from a SOHC in the "classified" section here on NICO. I don't think California and non-California models' ECU's are interchangable. So make sure before you buy from this guy or anyone.

http://www.nissaninfiniticlub....69066

[cf1203]

still have the 95 dohc auto ecu if anybody needs it. email me at [email protected]