Anyone previously tune on a 51Pxx 16-bit ECU ?

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rmp459
 

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Anyone previously tune on a 51Pxx 16-bit ECU ?

Post by rmp459 »

Having issues tuning a 95 Z32 TT. Car is running crazy rich at idle and my changed in nistune to K/Latency do not seem to affect the tune in the slightest.

I have been testing my stock tune, which the car just about quits on due to the injectors being set for 370cc. (I have 740cc) and a tune from a guy who has a lot of experience with Z32's but seems to mostly work w/ nistune in 8-bit scenarios. He built a tune for me from a 16-bit base file and when I try to change that tune, or adjust my stock tune to lean out the car a bit at idle... I get no response. I have tried value as low as 100 for K and as high as 250 and I get the same AFR... same with latency.. 750 up to 870 and no change at idle.

Car is just off a large maintenance and has no issues.. was 100% before injectors were swapped out and pretty much every hose/seal on the engine replaced. It is throwing no codes, and from what I can tell, nistune is working normally. For some reason at idle though, I occasionally see the knock fuel table light up green hued as if it is pulling from it, but never a knock sensor code.

Any ideas guys? I'm running out on my end.
Matt
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Re: Anyone previously tune on a 51Pxx 16-bit ECU ?

Post by Matt »

Had a look at the log files tonight. TP is hardly going above 8 so means K is way off. Try another log with K at half the stock value and send that through. AFRs seem also very rich for 1.5ms pulsewidth
rmp459
 

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Re: Anyone previously tune on a 51Pxx 16-bit ECU ?

Post by rmp459 »

Would it make sense that my issue w/ TP/load was due to incorrect scale maps for fuel/timing/etc. ?

I made adjustments with someones help and now have pretty good afr at cruise in 2nd/3rd and it richens up when boosting more like i'd expect. Still needs work in that dept and some 4th gear work.

On the flip side, my idle is still rich. Like 10.5-11 @ no less than 900-950 rpm. The car used to idle easily at like 800 on the 370cc injectors. My O2 sensors dont seem to be doing jack as when I look at the gauges the learn sits at 100 and the sensors themselves dont seem to fluctuate or do anything except read as rich. I seems to know its rich and still doesnt do anything about it. Feedback temps are back at 10, all o2 sensor bits are checked that are in the stock tune. Really wish I knew what was up with it... I think if I could get whatever my problem is resolved, fine tuning the fuel map would be no problem.
Matt
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Re: Anyone previously tune on a 51Pxx 16-bit ECU ?

Post by Matt »

I'll try and repeat on the bench tomorrow morning to see if I can get it behaving the same
rmp459
 

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Re: Anyone previously tune on a 51Pxx 16-bit ECU ?

Post by rmp459 »

Car just doesnt respond at idle.. i've tried like 3-4 tunes, resized the injectors a few different ways... unplugged the o2, plugged in the o2, checked voltages, temps, fuel pressure... injection time just sits up at like 1.8 and it bogs with a rich idle thats like 150 rpm above norm. Checked with like 3 tuners and none of them really have a clue.. no one nearby to get to either... man this sucks. It's like the injectors just refuse to lean out at all... and the narrow band O2 sensors ohm out identically, but just sit idle at their reading, they dont pulse at all.

Matt, could the ENT file have anything to do with it? My car is a 95 300zx TT, the original ECU was a 51P00.... this ECU I am using is from a JDM car and is a 51P60...it was also sent over to me with a 51P60 image on it.

Starting to think I should have opted for an 8-bit ecu and a type 2 board, speaking of which, can you install nistune on an already chipped 8-bit ecu?
Matt
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Re: Anyone previously tune on a 51Pxx 16-bit ECU ?

Post by Matt »

With the orginal file that you emailed through with the 16 bit sp conv, I was concerned about TP being stuck so low. Your trace cursor doesnt seem to want to get past the first two columns which is unusual

I now see this one the bench. AFM voltage needs to get upto about 2-2.5 volts with revs @ 2500rpm before TP starts increasing and the trace goes right

However even before this I'm seeing from your log the AFM (MAF) plateau at about 1.8volts and it doesnt seem to be wanting to read any more load even though its on 11:1 AFR (so not because its running lean)

Is the MAF okay? I would be expecting it to read higher than what it is. ECU

Your ECU at 1.8 volts MAF and 3200 rpm is showing 1.8ms for 740CC and with the stock image loaded in the same point is 2.4ms on the bench because of standard injector size) so I would say that the decreased injection is normal considering where K constant is at

The fact that your log is showing a flat MAF line during acceleration is concerning. Would suggest checking vacuum leaks, intake piping and perhaps swapping over another MAF
eduardo
 

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Re: Anyone previously tune on a 51Pxx 16-bit ECU ?

Post by eduardo »

I am the official ecu tuner at concept Z performance in AZ USA, and I managed to find the solution for this problem. We sold one 16bit nistune upgrade to one user who used a nistune rom pack to flash another bin file in it, now the thing is messed up.

The 16bit base files are not good in nistune rom pack. Solution to this is prior to soldering, extract the stock 64kb file from your stock ecu using "TECU" software, then select range 0000 to FFFF, this will download the whole base tune from your 16bit Z32 ecu. Then use your original base tune to flash into the board. But you need base tune flasher for this.

Matt should add a feature where one can download the base tune from his original ecu first. Because I can't seem to fin the TECU software anywhere now.

In another words base tune has to be specific to that ecu. for example 53P00 in australia will have different base tune than 53P00 in north america. You can't run 53P00 in 53P01 ecu at all
Matt
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Re: Anyone previously tune on a 51Pxx 16-bit ECU ?

Post by Matt »

Duplicated post. Response here
viewtopic.php?f=11&t=2375
rmp459
 

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Re: Anyone previously tune on a 51Pxx 16-bit ECU ?

Post by rmp459 »

Just incase anyone else reads this thread, i'd like to post some sort of conclusion.

After working with Matt a bit and some local contacts/tuners here in the states, I was not really able to get the type-3 board to respond the way I wanted it to. We/I tried to rebuild 16-bit files from scratch to get it to work, but no progress. There were some things that did "sort" of work... specifically the injector latency and the K value did make some difference, but it did not work as it was supposed to.

I could never get my idle afr above 10.5 or so regardless of what I did. I tried adjusting the K value from 160ish down to like 100 and up to like 250 and it really didn't make much of a difference. As I approached the K value for 370cc injectors (I have 740cc nismos) it would resist starting and idling, but there was so little sensitivity that I couldn't really tune the car.

Still entirely possible I was doing something wrong, but after testing my tune converted to 8-bit via eprom in a friend's ecu I just decided to scrap the 16-bit idea. I was lucky enough to swap out my 16-bit nistune board for an 8-bit one... moved the tune over and I couldn't be happier.

Had the car dyno'd and the tune cleaned up a bit a few weeks ago and made ~360whp/~400tq @16.5psi. Tune is pretty conservative and had no indication of knock at this boost level. Pretty happy considering im still on a single pop intake and stock turbos. Might make a little more power with a dual solenoid boost controller, like a blitz type r, since I am seeing a 2-3psi fade on the dyno from peak boost to redline. Another thing to note was that it was 97F/36C ambient temp on the day I got dyno'd... not really ideal.. heh.

Matt, wanted to say thanks again for the constant back and forth and helping me get things sorted.
Matt
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Re: Anyone previously tune on a 51Pxx 16-bit ECU ?

Post by Matt »

Given the problems experienced with tunability of this ECU after upgrading injectors, as of this week I'm dropping 16 bit Z32 ECU from the website to avoid any further issues. This is after discussion with another tuner here in Australia via email with the same problems and control issues

Whilst admittedly the K const and injection multiplier have an effect, when changing it sufficiently for larger injectors (in three cases 740CC, 740CC, 800CC) the AFRs seems to be hitting a wall

There is something in particular with this ECU when upgrading the injectors, resulting in TP shifting is messing up the tune. There could be another table which requires modifying perhaps in the ECU code,

It seems to be an injection limiting condition being hit outside the current defined set of tables (including TTPmin/TTPmax) but I'll look into it further in the meantime
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