Help With My Nismo Ecu.

[Lakes101]

Morning gents. So after finding a replacement o2 sensor for my m35 and installing it yesterday I thought I'd plug my nismo ecu in and see how she would run now with no error codes but still to my bitter disappointment she fired up running rough and then stalls I checked again for any error codes and nothing.

Any ideas as to why I wouldn't be running and stalling with the nismo ecu I'm scratching my head as ivegone over everything!! Thought it could be fuel related so checked fpr's fuel pump and for any leaks but nup all is good.

Please guys throw some help my way I'm dying to get this ecu in and running perfect

Edited June 13, 2014 by Lakes101

[ironpaw]

I thought someone has already suggested that not all nismo ECU's are created equal...so maybe your ECU has a map for an M35 running different hardware?

[Duncan]

I'm not at all familiar with the m35 nismo ECU....but in all other nissans I know of the nismo ECU it is just a modified standard ECU.

If it's the same, it is almost certainly a faulty ECU, nothing to do with the fact it is nismo modified or not.

[Lakes101]

It was running out of bricks car sweet and from what I've looked up nismo ecu's have just a default maps on them and are all the same.. Not like impul or the like.. If it is the case that it has a different map what would the suggestions be as to get the idle smooth and running right?

[Duncan]

well if you know it was working in another car that is much easier. by far the most likely reason to not idle with a changed map would be different injector or AFM size but I guess you would know that already from the other car

[Lakes101]

Ok well is there any one in the Sydney area today that would want to help me out and see if it runs in there car at all its the only way I can think of to see if it's faulty or not??

[Daleo]

It's my understanding that the NM35 Nismo ECU was a custom map, written for the specific vehicle it was fitted to. This is why we can't just buy a reflashed ECU from Nisan/Nismo to suit.

If you bought one from a car that had minimal mods; you're good to go on a local car built to a similar standard.

If however; you managed to get one from a more seriously modified car (larger injectors, higher fuel press, etc) you will essentially need to match the mods to achieve the same result.

I realise this doesn't really help you, but there is always risk inherent in purchasing stuff like this; most that I've seen, have been awesome, and a real improvement over stock, but there's always the chance of it not being perfect without mods first.

[Commsman]

I might have missed this, but is the car running properly with the standard ECU installed, ie just plays up with the Nismo?

What mods did Brick's car have when it came out & was it OK when he had it?

[Lakes101]

Yep runs perfect with the stock ecu just idles shit and stalls with the nismo well I'd idles ok but eventually stalls it sits about 550rpm for about 20 seconds in park then stalls.

I'm sure brick only had a highflow and fmic on his when he had it with the nismo ecu.

[iamhe77]

What Dale states is correct. Nismo custom tune to the customers car (I enquired to purchase one years ago and they refused unless I could get my car to them).

What are the mod differences between your car and Bricks?

[KiwiRS4T]

Firstly stick your stock ecu back in to make sure something hasn't gone wrong.

If that runs well then the only sure way to check the Nismo ecu is to put your car on a dyno and see what's going on.

[Commsman]

Yep runs perfect with the stock ecu just idles shit and stalls with the nismo well I'd idles ok but eventually stalls it sits about 550rpm for about 20 seconds in park then stalls.

If you keep the revs above 650-700 via throttle position will it 'idle' longer? I'm wondering if a simple idle reset/relearn or idle rev increase via UpRev would fix it (if that is all that is wrong)?

I fail to see how having a hi-flow or not will make enough difference at idle.

Edited June 13, 2014 by Commsman

[iseekool]

@OP - Check out the throttle position sensor after you have tested with a stock ECU

[Lakes101]

Yeah If I manually keep the revs up via the peddle it doesn't conk out. I've done the idle reset/relearn three times but to no evail. Plugged back in my stock ecu and all is well so I'm stumped as to what is leaning it out so much it even stalls if I have to break hard and revs drop to low which can be quite perilous in heavy traffic. Is the any.one that would be willing to let me plug it into there car and see how it runs?

[scotty nm35]

You need to get a wideband up the exhaust, to see how rich or lean it's running. I suspect it was set up for larger injectors or something. If that's the case, you will need an Emanage or similar to adjust the fuel map.

It could have also been setup to run a Z32 afm or similar... It could even been MAP tuned, but I doubt it. Only the dyno could tell you, but without means to adjust it you can only throw parts at it to test I guess.

[DaveM35]

We're kind of talking in circles with this...

I feel sorry for you that you forked out a lot of money for it and it never worked good, that's the risk we take buying second hand stuff.

Now the only way you might ever get it to work is by doing what Scotty said and adding something else (piggyback ecu) that can adjust your maps. But we've suggested that several times before.

What you would like to happen and what needs to happen seem like different things, in not trying to be harsh bro, really I feel bad for you but that is keeping it plain and simple.