So who wants their ECU's "Chromed"?

[99 vr4]

It was blackstealth who made it. I know not ALL 98-99 montero ECUs are flashable, but some are. Blackstealth chose by part number and they have knock circuits built it. At the same time I bought a friend 99 3.5L montero ecu, he put into his USDM stealth and his car runs and drives great. I'm using a 98 montero 3.8L ECU I think.

These 98-99 Montero ECU part numbers don't need modification because they have knock circuits built in.
MD343513
MD361885
MD365261

Blackstealth told you wrong. Sorry. That is why you are having problems. I modify these ECUs all the time.

The knock circuit is PARTIAL. They are MISSING critical throttle position components. They are MISSING secondary O2 circuits. The ECU can only see the rear bank. (I know you said you are JDM, but you will mislead other people) And they are MISSING a ton of other stuff. You should not listen to those that don't really have a clue. Ask Adam, Aaron, Greg, or Jeff if you don't believe me.

Also, the 99 Montero is different than the 98 Montero. At least the 99 has the throttle position circuits. But again, single bank trim, and missing a multitude of other circuits. Good luck.

And in my opinion, you are stupid to even try this, and then ask for help, and not listen to what those that know more than you are telling you. Get a proper ECU, at least an SL. Don't be cheap. But hey its your motor. Do what you want.

I am off my soapbox.

[vr4whore]

Blackstealth told you wrong. Sorry. That is why you are having problems. I modify these ECUs all the time.

The knock circuit is PARTIAL. They are MISSING critical throttle position components. They are MISSING secondary O2 circuits. The ECU can only see the rear bank. (I know you said you are JDM, but you will mislead other people) And they are MISSING a ton of other stuff. You should not listen to those that don't really have a clue. Ask Adam, Aaron, Greg, or Jeff if you don't believe me.

Also, the 99 Montero is different than the 98 Montero. At least the 99 has the throttle position circuits. But again, single bank trim, and missing a multitude of other circuits. Good luck.

And in my opinion, you are stupid to even try this, and then ask for help, and not listen to what those that know more than you are telling you. Get a proper ECU, at least an SL. Don't be cheap. But hey its your motor. Do what you want.

I am off my soapbox.

I just followed what blackstealth told me to buy, I didn't get to read this forum until recently.

[BlackStealth]

A while back vr4whore was searching for a flashable ECU, no VR4 ECU or SL ECU, or cloned ECUs were available for purchase. He asked for help in locating a flashable ECU and the only thing available at that time was Montero ECU and nothing else. There are many Montero ECUs available each needing different hardware modifications. I recommended vr4whore to purchase the same Montero ECU part number that Jesters Deadd sold a while back as a good starting point ( 3000GT/Stealth International Message Center ). It reads "I have a MD343513 which is the 98 Montero LS ECU. It has the knock sensor and two O2 sensors. This is probably the third best ECU to have for the flashing ability that the 98-99 VR4s have. THe first being the 98-99 VR4 ECu, the second being the 98-99 SL ECus."


There is absolutely nothing wrong with my recommendation, it is still correct. It just needs more work than a 3000GT VR4 or SL ECU.

I have already told vr4whore his stalling is from the open BOV, he went from speed density to MAF.

One of the reasons his car is running lousy is because he did not address the low/high voltage fuel relay pump. His fuel pump will run at low voltage because he does not have a VR4 ECU to switch over to high voltage mode, and is dangerous to drive like this. Replacing the low/high voltage fuel relay with a jumper wire arranged such that the fuel pump receives full voltage is a quick and easy fix. This is not optional, it must be done. "Boosting gently" will cause fuel starvation and the car will drive horrible as expected.

Flash tuning is a bit intimidating for some people, so I will generate a flash rom image with their injector size, injector latencies and disable some peripheral bits to get them started.

Using HHH-Hybrid to pull codes on the 98/99 flash ECU does not work correctly, and the error codes they generate should be ignored as it will lead you astray with misinformation. To pull codes reliable use OBD2 mode only.

To fix v4whore car I would do this:
(1) Get that low/high voltage fuel relay replaced with a jumper wire. EDIT: This is not necessary, it is at high voltage by default.
(2) Get that open BOV to closed/recirculated BOV.
(3) Get a WBO2 controller and disable all O2 (open loop mode only). My car has been running open loop mode only for more than a year and to my surprise it works very well in this mode. The best part of open loop mode is that no O2 circuit modifications are necessary. A WBO2 is needed to verify open loop mode is working fine and if not, adjustments to the injector scaling can be tweeked to make it so.

[Jesters Deadd]

A while back vr4whore was searching for a flashable ECU, no VR4 ECU or SL ECU, or cloned ECUs were available for purchase. He asked for help in locating a flashable ECU and the only thing available at that time was Montero ECU and nothing else. There are many Montero ECUs available each needing different hardware modifications. I recommended vr4whore to purchase the same Montero ECU part number that Jesters Deadd sold a while back as a good starting point ( 3000GT/Stealth International Message Center ). It reads "I have a MD343513 which is the 98 Montero LS ECU. It has the knock sensor and two O2 sensors. This is probably the third best ECU to have for the flashing ability that the 98-99 VR4s have. THe first being the 98-99 VR4 ECu, the second being the 98-99 SL ECus."


There is absolutely nothing wrong with my recommendation, it is still correct. It just needs more work than a 3000GT VR4 or SL ECU.

I have already told vr4whore his stalling is from the open BOV, he went from speed density to MAF.

One of the reasons his car is running lousy is because he did not address the low/high voltage fuel relay pump. His fuel pump will run at low voltage because he does not have a VR4 ECU to switch over to high voltage mode, and is dangerous to drive like this. Replacing the low/high voltage fuel relay with a jumper wire arranged such that the fuel pump receives full voltage is a quick and easy fix. This is not optional, it must be done. "Boosting gently" will cause fuel starvation and the car will drive horrible as expected.

Flash tuning is a bit intimidating for some people, so I will generate a flash rom image with their injector size, injector latencies and disable some peripheral bits to get them started.

Using HHH-Hybrid to pull codes on the 98/99 flash ECU does not work correctly, and the error codes they generate should be ignored as it will lead you astray with misinformation. To pull codes reliable use OBD2 mode only.

To fix v4whore car I would do this:
(1) Get that low/high voltage fuel relay replaced with a jumper wire.
(2) Get that open BOV to closed/recirculated BOV.
(3) Get a WBO2 controller and disable all O2 (open loop mode only). My car has been running open loop mode only for more than a year and to my surprise it works very well in this mode. The best part of open loop mode is that no O2 circuit modifications are necessary. A WBO2 is needed to verify open loop mode is working fine and if not, adjustments to the injector scaling can be tweeked to make it so.

99VR4 is correct the montero ecus don't have the knock circuit. I actually opened that ECU before I sent it out and found out it was missing the knock circuit. I fixed it and several other circuits before I sent that ECU out. I communicated that with the guy I sold it too but didn't post in the thread. I can fix that old thread.
If anyone has questions on these ECUs 99vr4 and/or I have pretty much seen it all at this point, since we are the only two guys selling/making full vr4 ECU clones.

[Greg E]

To fix v4whore car I would do this:
(1) Get that low/high voltage fuel relay replaced with a jumper wire.
(2) Get that open BOV to closed/recirculated BOV.
(3) Get a WBO2 controller and disable all O2 (open loop mode only). My car has been running open loop mode only for more than a year and to my surprise it works very well in this mode. The best part of open loop mode is that no O2 circuit modifications are necessary. A WBO2 is needed to verify open loop mode is working fine and if not, adjustments to the injector scaling can be tweeked to make it so.

I might be wrong, but I think the default position for the relay is "HIGH". The ECU triggers a ground using the port B data register which switches the relay.

Open loop tuning is fickle. It seems you always need to tweak it... I have played a lot with it but it's really nice to have the O2s get things in running condition for you so you can have an easier time adjusting the MAF/Injector tables to bring the trims within 5%. The auto tune feature (closed loop) is one of the most powerful features of the ECU. In fact, I'm working on a patch to extend closed loop beyond it's current load limitations so the ECU can auto tune for a specific AFR using the wideband during WOT.

[Greg E]

My peripherys inputs don't seem the same, for example I have a input for rear o2 sensor?

Periphery 0 & 2 are mislabeled in chrome V1. My apologies for this. It was taken from someone else's disassembly and I took them for granted as I wasn't very familiar with how the OBD2 code worked back then. Chrome V2 will have everything labeled correctly and I have tested each one on my car to verify functionality.

LEAVE PERIPHERY 0 STOCK! DO NOT CHANGE ANYTHING even if you have deleted the systems! The bits are tied into multiple areas of the code which effect the IPW calculation and will cause your car to run like ass.

Periphery 2 and 3 control the DTC functionality of the ECU. These are what you switch off to disable CELs for missing sensors.

[Greg E]

If you guys open up your 23861xx6 XML, replace the periphery tables with this:

		<scaling name="EnableDisableBit" storagetype="bloblist" storagebits="1">
		<data name="Off" value="00"/>
		<data name="Enabled" value="01"/>
	</scaling>
	

<table name="ECU Periphery0 Bits (272) +0" category="Periphery" address="10272" type="2D" scaling="EnableDisableBit">
		<table name="Periphery Bit Number" type="Static Y Axis" flipy="true" elements="16">
			<data>bit.15                                               .</data>
			<data>bit.14  O2 Heater Functions                          .</data>
			<data>bit.13                                               .</data>
			<data>bit.12  Purge function                               .</data>
			<data>bit.11  EGR function                                 .</data>
			<data>bit.10  Timing Retard on Accel                       .</data>
			<data>bit.09  Cat Warmup Ign Retard Function  (Leave OFF)  .</data>
			<data>bit.08                                               .</data>
			<data>bit.07  Knock Sensor/Octane Functions                .</data>
			<data>bit.06  Speed Limit Function                         .</data>
			<data>bit.05                                               .</data>
			<data>bit.04  Closed Loop function                         .</data>
			<data>bit.03                                               .</data>
			<data>bit.02  OBD2 Bytes A and C                           .</data>
			<data>bit.01  OBD2 Bytes B and D                           .</data>
			<data>bit.00                                               .</data>
		</table>
	</table>

	<table name="ECU Periphery1 Chrome Mods Bits*" category="Periphery" address="10282" type="2D" scaling="EnableDisableBit">
		<table name="Periphery Bit Number" type="Static Y Axis" flipy="true" elements="16">
			<data>bit.15                                               .</data>
			<data>bit.14                                               .</data>
			<data>bit.13                                               .</data>
			<data>bit.12                                               .</data>
			<data>bit.11                                               .</data>
			<data>bit.10                                               .</data>
			<data>bit.09                                               .</data>
			<data>bit.08                                               .</data>
			<data>bit.07                                               .</data>
			<data>bit.06                                               .</data>
			<data>bit.05                                               .</data>
			<data>bit.04                                               .</data>
			<data>bit.03                                               .</data>
			<data>bit.02                                               .</data>
			<data>bit.01                                               .</data>
			<data>bit.00  Chrome Mod Lean Spool                        .</data>
		</table>
	</table>

	<table name="ECU Periphery2 Bits (292) +0" category="Periphery" address="10292" type="2D" scaling="EnableDisableBit">
		<table name="Periphery Bit Number" type="Static Y Axis" flipy="true" elements="16">
			<data>bit.15 P0443 P0446 P0403 P1104 P1105 Solenoids Test  .</data>
			<data>bit.14 P0450 Fuel Tank Pressure Sensor Test          .</data>
			<data>bit.13 P0442 Evap Incorrect Purge Flow Test          .</data>
			<data>bit.12                                               .</data>
			<data>bit.11 P0135 P0141 P0155 P0161 O2 Heater Test        .</data>
			<data>bit.10 P1400 MAP Sensor Test                         .</data>
			<data>bit.09 P0403 EGR Solenoid Test                       .</data>
			<data>bit.08 P0505 Idle Control System Test                .</data>
			<data>bit.07 P0170 P0173 Front Rear Fuel Trim Test         .</data>
			<data>bit.06 P0125 Excessive Time to Enter Closed Loop     .</data>
			<data>bit.05 P030x Misfire Detected (set with bit 4)       .</data>
			<data>bit.04 P030x Misfire Detected (set with bit 5)       .</data>
			<data>bit.03 P0136 P0156 Front Rear Secondary O2 Sensor    .</data>
			<data>bit.02 P0130 P0150 Front Rear Primary O2 Sensor      .</data>
			<data>bit.01 P0421 P0431 Warmup Pre-cats Efficency Low     .</data>
			<data>bit.00 ALL OBD2 DTC Lookups                          .</data>
		</table>
	</table>

	<table name="ECU Periphery3 Bits (2A2) +0" category="Periphery" address="102a2" type="2D" scaling="EnableDisableBit">
		<table name="Periphery Bit Number" type="Static Y Axis" flipy="true" elements="16">
			<data>bit.15                                               .</data>
			<data>bit.14                                               .</data>
			<data>bit.13                                               .</data>
			<data>bit.12                                               .</data>
			<data>bit.11                                               .</data>
			<data>bit.10                                               .</data>
			<data>bit.09                                               .</data>
			<data>bit.08                                               .</data>
			<data>bit.07  P0551 Power Steering Pressure Sensor Circuit .</data>
			<data>bit.06  P0500 Vehicle Speed Sensor Malfunction       .</data>
			<data>bit.05                                               .</data>
			<data>bit.04                                               .</data>
			<data>bit.03                                               .</data>
			<data>bit.02  P1103 WasteGate Actuator Malfunction         .</data>
			<data>bit.01  P0510 Closed Throttle Position Switch        .</data>
			<data>bit.00  P1600 Battery Voltage Low                    .</data>
		</table>
	</table>

These are the correctly mapped bits.

[Jeff V.]

One of the reasons his car is running lousy is because he did not address the low/high voltage fuel relay pump. His fuel pump will run at low voltage because he does not have a VR4 ECU to switch over to high voltage mode, and is dangerous to drive like this. Replacing the low/high voltage fuel relay with a jumper wire arranged such that the fuel pump receives full voltage is a quick and easy fix. This is not optional, it must be done.

This is exactly why flash tuning on these cars is such a mess. We have platform 'experts' posting blatantly WRONG info.

Simply looking at the schematics in the service manual, combined with some common sense, is all that is necessary. I'm pretty sure Jeff Lucius covered this at length on his fuel pump page too.

The relay position defaults to HIGH speed. The ECU has to force it to the low position. If the relay ever failed, the engine is still safe. I'm disappointed that I have to point this out to someone who designs and sells electronics.

If one our experts is getting such BASIC info wrong, what other bad info is out there?

[Jesters Deadd]

This is exactly why flash tuning on these cars is such a mess. We have platform 'experts' posting blatantly WRONG info.

Simply looking at the schematics in the service manual, combined with some common sense, is all that is necessary. I'm pretty sure Jeff Lucius covered this at length on his fuel pump page too.

The relay position defaults to HIGH speed. The ECU has to force it to the low position. If the relay ever failed, the engine is still safe. I'm disappointed that I have to point this out to someone who designs and sells electronics.

If one our experts is getting such BASIC info wrong, what other bad info is out there?

I don't think it it such a mess. Just a simple mistake/ misunderstanding.
It would be nice to have a place where the information could be posted and only edited by certain individuals. Then you could avoid the repeated questions and misinformation. Make a wikipedia of 3000gt flash tuning.

[Chris@Rvengeperformance]

I don't think it it such a mess. Just a simple mistake/ misunderstanding.
It would be nice to have a place where the information could be posted and only edited by certain individuals. Then you could avoid the repeated questions and misinformation. Make a wikipedia of 3000gt flash tuning.

maybe he could start a flash thread in the "build" section. It is nice we can at least edit our posts here.