TOYOTA engine swaps, avoiding wiring job traps

Since I have started developing TOYOBD1 I learned constantly about the 90s to mid 90s OBD1 Toyota ECUs, they all share similitudes.The traps we fall into while doing custom engine wiring jobs are also similar here are a few I have encountered through the years that may save you time and money.

The STA wire

STA is not to be fed with a constant 12v source like b+, it's purpose is to inform the ECU that the starter is engaged while the starter is engaged. feeding constant 12v to STA will fool the ECU into thinking it is cranking all the time, regardless of engine speed.this will make an ECU inject about 2.5 times the fuel it would have injected normaly. in all cases I have seen it is so rich the ignition cannot burn all that fuel, and of course engine performance is bad. Lots of people fall into that trap, stay aware!.

The Batt wire

This one is a constant 12v power source, it is fused and always powered regarless of ignition key position. this is what keeps the RAM (ecu memory) powered at all time. not feeding Batt correctly will result in Error codes being wiped every time the engine is shuted off, and the ECU learning process starts form scratch every time. 

Digital 3 wire TPS (PSW, E2, IDL)

On cars using this system it is important that those signal be wired correctly. those ECUs dont have a real TPS, this TPS design only tells the computer if you are at idle, at WOT , or anywhere in between. this is a lot of guessing and if the ECU senses the throttle is at WOT when it is not it may take bad fueling and ignition angle decisions. a digital tps can also simply go bad and need replacement. found on MT cars 3S-FE,4E-FTE,etc

The E2 wire

This is a special ground,This is the sensors ground, this ground must not be tied to other ground signals directly, doing so may introduce sensor noise or worst.

OBD1READ + TOYOBD1 :: making sure it works for your specific case prior purchase!

There is lots of  combinations to be done so let's clear out if TOYOBD1 will work with yours! Here are 5 steps to find out like a pro.

 

1- Is your car standard and listed under the supported engines list? 

if not, it may be supported but you should ask me advices so that we sort it out.

 

 

2- You need an android device

 

Phones and tablets with Bluetooth capabilities using running Android 2.2 or higher will do.
SD Card external storage capability is highly suggested for use of the import/export features.
take the time to install the TOYOBD1 application and familiarize yourself with the menu and the very informative glossary.

 

3- You need to find 4 signals in your ECU pin out 

You need to know your exact ECU pin out, it may differ from market to market and even from car model to another model WITH the same engine, or between Manual transmission and Automatic transmission. if you cannot find your ECU pin out online you can open your ECU and take a look at the pins label on the bottom PCB. please share your unavailable pin out findings so that we live in a better world :)

when looking at an ECU pin out you want to see TE2,(VF or VF1), E1 and B+. OBD1READ needs those 4 signals to work. if you don`t have a TE2 signal it will not be able to work at all.

 

4- You need to know your diagnostic box on your car( this is where OBD1READ connects )

You need to find it and identify what signals are available there, otherwise you will need to source them elsewhere. The sticker in the cap can be misleading, it will tell you where each signal is housed but it will not tell you if it is present.That sticker is universal for toyota cars of a specific era. The signals you are after are VF1,B+,E1 and TE2 please be careful many persons mistook TE1 for TE2, they are physically near and almost named identically...beware!( no harm to the device can be done if you connect te1 instead of te2)

You need to probe in those spaces with something small enough like a micro screw driver, you are searching for metal contacts. if some are missing, (TE2 is generally the missing one) you need to source that signal from elsewhere. either on ecu pins through new wires or by splicing into existing wires at the ecu connectors. the 1UZ-FE engine swaps mostly always need to take the TE2 signal this way.

 

5- You have found your signals, you can test if they do useful work

Using this test method you can determine if your ECU can be put into obd1 data output. it requires a digital multimeter( a test light is not a proper tool for this)

 Summary

At this time you should have an android device ready with TOYOBD1, You have an ECU that was proven to output OBD1 data when TE2 and E1 are jumped together AND you know where to source your signals.
It is safe to say that an OBD1READ device with TOYOBD1 will work for your car!

Testing toyota fuel injector Wiring with a paperclip

Using a paperclip you can test the basic operation of gasoline fuel injectors.

NEVER DO THIS TEST WITH A RUNNING FUEL PUMP IT WILL INJECT FUEL IN THE CYLINDERS.DISABLE FUEL PUMP FIRST

this information is targeted at TOYOTA designs but should be meaningful for many other makes.

this test can reveal:

• the injectors cannot be actuated by the ECU(if you can't manually it cannot either)
• one or many injector are clogged (don't click when powered)
• the injector you are actuating is matching the one that is  clicking, (in custom engine swaps those injector wires can be inadvertently exchanged)

this test cannot reveal:

• current applied at the positive pin of the injectors is sufficient(too low current caused by bad resistor pack or bad wires on the 12v side)

So overall it can tell you that if you can't actuate the injectors manually the ECU wont be able either...

It can be performed on a car or a bench test setup. The following video shows it on a bench setup.

Theory behind the test

On conventional designs, the fuel injectors have 12v current applied on their positive pin when the ignition switch is ON. the negative pin of each injectors is connected to an ECU which sinks that current when the ECU wants to actuate that specific injector.

Without an ECU installed but having the ignition switch at ON you can sink an injector current manually by jumping an injector contact at the ECU connector with a main ECU ground contact  at the ECU
connector. doing this will result in a clicking sound coming from that particular injector when the jumper is placed or
removed.

Getting started with the JVF2010A

OK, so you bought a JVF 2010A panel for cheap, you don't know how to use it and you got here while searching how to!

The JVF 2010A is an 80s computer that execute a DOS program that is placed on a properly formatted Floppy disk, You simply place the floppy in the drive, power on the panel , it takes a time to boot and after this it displays the default animation continuously.That system allows you to display animations that you will create or copy onto the floppy disk. You will notice an AT keyboard port on the side of the panel. you can edit your drawings and scripts directly on the panel in the main program, it's doable but I don't encourage this because we can do everything we need on the PC where the content to display will come from...

first you need to create a floppy disk that will have the basic programs and files to run.
The following archive JVF 2010A formating tool was found at http://johniii.tripod.com/jvf.html
there is lots of info on this page on how to write scripts with special effects,this subject is of course more advanced than the basics.

Using the 2010a.exe application found in the archive you can create floppy disks that will be formatted correctly and it will have the needed files/programs for the panel to work.

 You can now add new drawings and animation scripts to your floppy.

the main files types are as follows

*.DSN those are drawings, I would guess DSN comes from the french word 'dessin' since the company was based in QC,Canada... just a guess
all DSN files are kept in A:\DSN

*.SHW this is an animation file that contains commands that tells what to draw, what special effects to do and more.
all SHW files are kept in A:\

AUTOEXEC.BAT this is a batch file that gets executed when the system boots it contains the name of the animation file that will be ran when the panel is powered up.
AUTOEXEC.BAT is kept in A:\

(JVFA.exe or JVFF.exe) this is the program that does all the work.

How to add new content to the disk

In a prior blog post I was showing the DSNEditor windows application that I wrote. That application allows  the user to convert .bmp files to .dsn and generate a basic animation script at the same time. Using this tool I generated the animation that is shown in the video.

The files needed to play it are available in the following archive files. 

Simply extract the content on the A: drive. It will place the needed dsn and shw files where they belong and it will overwrite the AUTOEXEC.BAT file

After this just place the floppy disk into your panel and power it up, after 10 to 15sec it should start to play the animation or display an error message if something went wrong.

Another blog post will explain how to use DSNEditor to generate your own content...

Troubleshooting OBD1READ :: determine if the ECU is sending data

Testing if your Toyota ECU is outputting obd1 data is easy and requires only a digital voltmeter and jumper wire. Here's how to do this test.

-the ignition key must be at ON position and the engine not running.

-make sure there is no jumper wire between E1 and TE2 (no continuity present)

using the Voltmeter you must read the voltage between VF1(positive probe) and E1(negative probe). You should see a flat reading near 0V like in this video.

-Install a jumper wire between E1 and TE2.

using the Voltmeter you read once again the voltage between VF1(positive probe) and E1(negative probe). This time you will see an irregular fluctuating reading between 0V and 5V. this means a data stream is sent through the VF1 pin.

 

Using this method you were able to determine if your ECU is sending data that can be read for an OBD1READ device.

TOYOBD1 Android Datalogger :: Exporting data out of TOYOBD1

With TOYOBD1 it is possible to export data out of your Android phone.

Why for?

• to import in a spreadsheet program for custom calculations.
• to import back in another Android cell phone, say a friends phone for playback.
• to share TOYOBD1 data with a CarTester8000 users.
• to build an approximation of Ignition and Fuel maps from past recorded data.
• to have a backup files.

 First of all lets understand how the TOYOBD1 data is kept inside your Android phone.

TOYOBD1 uses an SQL database to store every log entry that was received from your OBD1READ device. It allows to record huge amount of data and makes it easy to precisely extract only what is meaningfull in specific conditions.

The design of the database makes it possible to keep log entries recorded with your phone and from someone else's phone without conflict and duplicate data. it also makes it possible to extract only specific data between a start date and end date.

Let's Export something  now!

Prior to exporting, a field need to be inputed in the Engine Configuration Dialog.
it is the 'Your car's description' field. You want this to be human readable for the people to whom you would send your log file for import.

for instance here are suggestions:
John Doe 4A-GE AE101
ZF 1UZ-FE SC400

when exporting data you will need to choose what kind of file you want to generate.

• CSV file for spreadsheet applications and TOYOBD1 import feature
• CTR file for use with CarTester8000 PC application
• CSV spreadsheet ignition map file 
• CSV spreadsheet fuel map file
• CSV spreadsheet both ignition and fuel map file

Next is the file name.By default a unique time based filename is suggested, change as needed.

The suggestd start date is by default a week ago, change as needed.
The suggested end date is by default today, change as needed.
The source, this is where you choose a car's description from the existing description
The ecu ID, you must remember what was your ecu ID number and choose it now.

when everything is choosen you simply press the 'Export Data' button.
processing time will vary depending on how much data is found for the search criterias you selected.
(this process can take minutes to complete if you export more than a month of data)

Dirt cheap portable MAF sensing

A while ago I realized that a portable MAF sensor would be nice to have. That sensor can be useful to sense engine health or how well it can perform. The idea came to use a junkyard OBDII ECU who came equipped with a MAF sensor.

 An OBDII ECU?

Here are some advantages to go down this route

• to get quantified readings from the sensors,no need to discover the OBDII sensors curves. You simply request a particular sensor reading. for instance what interest us today is the MAF sensor reading which returns a g/s flow rate.
• It is easy to interface an OBDII ECU to a PC or cellphone.
• It is easy to find a suitable ECU + matching MAF sensor in a junkyard for cheap
• There is many software options to interface to OBDII ECUs.

As I am a Toyota fan I looked toward the Toyota 3.0L V6 ECU using MAF sensors, what was available in junkyards at that time was the 1995 Camry 1MZ-FE ecu, that MAF sensor can be installed inline which helps when installing, that particular MAF sensor should be able to read engine air flow from comparable power levels engine which is sufficient this time.

How do we get this brillant concept to life now?

I choose to use the OBDII ECU as a portable unit, lying on the car floor, running a long cable to the MAF on the engine, getting power through the cigarette lighter port.

You need to build a minimalist wiring harness for this ECU to work on your car. Remember that you want just 3 things, the OBDII ECU, it`s MAF, and an OBDII connector, it really is not that hard to do, something like 10 wires.

After you made sure your ECU is powered correctly and all needed wires are going to their rightful places it is time to get some data out of that setup. The good old ELM327 comes handy for this, you can buy BT OBD2 adapters, USB obd2 adapters, probably even RS232 obd2 adapters, there is also many software out there to read data from an OBD2 ECU that can be used to glance at the data.

What to do with it then?

What I want to do with my MAF sensor is to plot unknown flow curve of various VAF sensor from non OBDII engine, comparing readings from the OBD2 ECU through time vs those of the unit tested.

(Take note to never install a MAF behind something that could make turbulence such as a VAF, you will get erratic readings... MAF in front of VAF gives good results!, take also note that this is a temporary test setup  )

And now the resulting flow curve for the VAF sensor