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late Pathfinder or Quest OBDII ecus on L eng?


HowlerMonkey

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Wow....great information.

 

How did you get around the ecu's expecting to see variable valve timing hardware on an engine that does not have variable valve timing.

 

If I knew for sure that I wouldn't have issues with this, I might jump into the coil on plug ecus with both feet and bail on my current line of thinking.

 

Right now, my horsepower needs are pretty low since this experiment is more on getting around 350hp and having it run clean enough to pass emissions regulations in a 1991 car.

 

Later on, I will be pursuing big HP and would love the opportunity to get rid of that crazy non-counterweighted distributor rotor since I feel it might be something else that could compromise high rpm spark events.

 

Speaking of high rpm events, I would love to find a way to sample all rpm and cylinder data from the crank and get rid of the slop associated with the oil pump/distributor drive shaft.

 

Most of the nissan ecus expect to see cylinder #1 pulse once per cam revolution instead of once per crankshaft revolution though I have not seen all nissan tone/shutter wheels used.

 

Going to crank trigger may be taking it too far though.........unless someone has done testing and has comparison data between a true crank triggered ecu setup and one that involves the distributor shaft.

 

Thanks for the contribution Jeffp, that is important information.

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How did you get around the ecu's expecting to see variable valve timing hardware on an engine that does not have variable valve timing.

 

You can turn off the valve timing very easily, or use it control an extra fuel pump, or methanol system or whatever.

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Also, don't forget about the THREE fan control lines that can be configured on a temp basis. I haven't messed with any of those outputs, they are a relay control line. I can check, but I do believe it is possible to adjust the temp settings to act like some other control line for whatever like Bernardd mentioned. Then if you get the 90-92 Twin Turbo ECU, then you have two additional outputs for boost control, so there are alot of options to play there to trigger a number of different devices.

 

The SLOP in the timing. I have looked into this some time ago and what I did was to match the gear,shaft, and oil pump take up the slop for the most part. I think I was seeing a deviation of about 1 degree of timing. I realize there are better ways to do the smae thing and get a fixed trigger off of the crank directly, but for the most part 1 degree of timing is not going to matter all that much. I NEVER run the car on the verge of pinging, I always back off the timing a degree or two just to give me a little safety margin.

I have thought about doing a trigger wheel of the stock chopper, just bigger to fit to the damper, but that is a little more involved then using a hall sensor.

The trigger setup Nissan used is an LED type configuration in the Infrared light spectrum. That is the challenge, getting the sensor on the damper, and sealing all of the light from outside away from the sensor. It may not be that critical, but I need to test a prototype to get the answer. I haven't had any problems triggering from the distributor, but it does take the turbo distributor and some modifications. I made a distributor for my car and I did a sceond unit for Bernardds car. I don't think he has any problems either.

So for the money, seeing that you can pick up an ECU off of ebay for under $100.00 dollars, then what the heck. The hard part is the harness, and if you are like me then you spend more on the harness then the ECU. I made my system totally plug and play for ANY 280zx turbo car. I also upgraded all of the EFI relays to a Nissan 80 Amp part, and for the O2 sensor, a 30 Amp part. I got both of the relays off of an M30 car for the anti lock brakes. I have the relays, the box, and cover to run my setup. I realize most people will not take the time to do that upgrade, as it is difficult to reuse the relay terminals, and solder them after you have them the way you want, but for me, that was the very best option I could find without spending another few hundred for a similar relay setup.

 

The Maxima and Z32 box solved all of my ignition problems, and the large injector latency problems that you may get with the older boxes from Nissan, and there again, there is a fix for that unit, but I did not want all of the added hardware to get the unit to operate the way I needed it to.

But, I have other concerns right now, like getting my fuel lines back from Classic tube. They really screwed up this upgrade for me, so I fired them and had my lines sent back to me, hell it only cost me about $100.00 in shipping to find out they were flakes, and I still have to get my lines completed.

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question: Is a J30 ECU the same as a 300ZXTT ecu?

 

I figure the J30 is the same as an N/A VG30DE ECU, but how different are those boxes than the TT version? Just missing the boost control? is that software or hardware? Is the ECU rigged for these controls and just not wired or are they not there altogether?

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question: Is a J30 ECU the same as a 300ZXTT ecu?

 

I figure the J30 is the same as an N/A VG30DE ECU, but how different are those boxes than the TT version? Just missing the boost control? is that software or hardware? Is the ECU rigged for these controls and just not wired or are they not there altogether?

 

No, the j30 ecu uses internal rom which requires a daughterboard. You're correct in that the NA vg and TT vg have the same layout with slightly different outputs and interchangable software.

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The reason I mentioned the TT CA ECU is that unit is populated with all of the hardware to run every option for the outputs. Nissan did not populate all of the components for other models of the same box. I could tell this was an early manufacture as most places did not populate all of the hardware back then.

That has changed in many cases with the use of the software options, and it is cheaper to manufacture one board then a number of boards.

The software, like Bernard mentioned enables, or disables various options and outputs as each model of car required.

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  • 1 year later...

I've started back up researching this which has become a quest to use obdII ecus that litter the junkyards of america and can be had for 30 bucks and the harnessing for about the same price.

 

I've settled on the quest/villager/frontier ecus for this reason.....and the fact that my current M30 ecu setup is getting hard to find anywhere.

 

The intent is to be able to flash the ecu through the OBDII port but I am having trouble finding anyone who makes an editor for the calibration files for these ecus and I believe the addresses for the critical values are in a different place making rev-up or osirus useless for this ecu family.

 

I guess it's time a huge amount of time to put the known values into the search dialog of a binary or hex editor so I can find where the values exist on these ecus......unless someone knows of an editor that has been successfully used on these ecus.

 

I really need to find an ecu for a supercharged frontier/xterra and see if I can run the non-supercharged ecus with these settings.

 

 

If you guys find one for sale, please let me know.

Edited by HowlerMonkey
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  • 11 months later...

It seems the pathfinder/quest/frontier family of ecus is a dead end until either nistune makes a board for them or someone releases a way to edit the "configuration file".

 

The intent was to find a good and never ending cheap source of ecus that could be flashed through the data link connector as in the 1999 and later ecus.

 

Nobody is offering any tuning for that family of ecus that I know of unless nistune released a new board recently though it is possible that 1999 and later ecus would be the best candidates since some nissan tuning suites for flashable ecus do go back that far.....but they don't mention any vehicle with this family of ecu.

 

That said, you could fit the harness and ecu from a supercharged frontier/xterra and run 260cc injectors untuned on your l28et but it's not worth the effort and you would still have to satisfy that ecu's need to see a crank angle sensor that reads the flywheel (used for obdII misfire and other diagnostics...but not the acctual running of the car)

 

You would have a check engine light without it.

 

It's obvious that the Z32 or maxima VE30de ECU coupled with nistune is way to go for coil on plug type goodness on a L28 while the standard L28et distributor type would work best with the M30 ecu or, if you don't need consult, the maxima single cam ecus.

 

Since the VE30de and the VG30de (non turbo) ecus as found in the maxima and Z32 already come with 260cc injectors (same size as stock L28et), both would be fine without tuning on the L28et at stock boost.......if you can satisfy the ecu with the waveform outputted by the factory CAS.

 

The VG30DETT, of course, has even larger injectors.

 

While the VE30de is relatively rare in junkyards, the same sensor (but with V8 encoder disc and slightly longer case) is available on the more commonly found in junkyards.

 

The VE30de disc will bolt into the Q45 sensor but you are still left with having to machine it so you can mount it to your L28 engine or take it apart and transfer both the disc and sensor to the proper fitting "distributor" of your choice.

 

Same goes for the VG30DE disc which seems to be exactly the same as the VE30DE disc but inside a different case.

 

The smaller diameter of the two discs means you can't simply swap them into a L28et distributor as you would a VG30 disc to run a z31 ecu unless you want to do what is necessary to fit the smaller disc and then fit or modify the sensor that can read it.

 

All of the ecus mentioned above would need dropping resistors to run the L28et low impedence injectors unless you can find some pretty rare top feeds from the CA18DE pulsar SE.

 

They are also a bit more rare to find and expensive than the original quest/frontier/xterra ecus and the wiring harnesses you could pull would be far older.

 

The goal of super cheap and abundant OBDII ecus and harnessing that will run on a L28ET using the VG30 encoder disc was not reached.

 

It seems this is another "earlier is better" story and I've long ago gone on to other ecus but wanted to finish out this thread.

 

If I do find a software suite that can inexpensively tune the late obdII ecus, I will post a further update.

Edited by HowlerMonkey
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