99 subaru ecu compatability

[tysn]

i had an earlier post on swapping a ej22 out of a 96 legacy into my 99  sus, we went back and forth getting the timing right, i finally got the timing right and i got the car running, it ran but it had a code for the crank shaft not being in sync with the cam, we replaced the crank sensor and the car ran beautifully for 15-20 minutes, then all of the sudden the car ran like crap, my mechanic buddy hooked it to his scanner and came back that there is no pulse to the #1 cylinder injector, so as you can imagine the car runs on 3 cylinders, he was lead to believe that the ecu has gone bad, will a ej22 ecu work in a 99 outback sedan running a 96 legacy ej22? assuming that both cars are automatics? are the pinouts the same?

[lstevens76]

A little research and reading goes a long way.  This is an endwrench article that is available from links in the endwrench sticky thread.

 

"Legacy And Impreza Engines With

No Injection Pulse #1 Cylinder
Built into the fuel injection control
unit is logic that will shut off the #1
injector if the computer believes that it
can no longer control the Idle Air Control
Valve. Remember this design characteristic
if you are trying to diagnose a “hard”
code for the Idle Air Control Valve or a
dead miss in the number one cylinder
due to no injection at idle. A problem in
the Idle Air Control Valve circuit may be
responsible. (Component testing shows
that it most likely is not the valve itself.)
Also, if the computer is deprived of its
“back up power supply,” some computers
will generate a false code for the Idle
Air Control Valve and kill the injector
End Wrench
14
End Wrench The
for cylinder #1. The pin location of this
power supply can be found in the Control
Unit Module I/0 Signal pages of the
appropriate Service Manual."

 

http://www.northursalia.com/techdocs/pdf/engine/emissions.pdf

[idosubaru]

what check engine light codes are you getting?

 

yes - a 1996-1998 EJ22 ECU will work, but not a 1999 EJ22.

interesting read up there about cylinder 1 signal and IACV, crazy

[matt167]

I had a 99 sus and did same swap. 96 2.2 and all. I thought a 99 legacy sus or outback had a one year only ecu because of the phase 2 trans and phase 1 engine electronics

[tysn]

A little research and reading goes a long way.  This is an endwrench article that is available from links in the endwrench sticky thread.

 

"Legacy And Impreza Engines With

No Injection Pulse #1 Cylinder

Built into the fuel injection control

unit is logic that will shut off the #1

injector if the computer believes that it

can no longer control the Idle Air Control

Valve. Remember this design characteristic

if you are trying to diagnose a “hard”

code for the Idle Air Control Valve or a

dead miss in the number one cylinder

due to no injection at idle. A problem in

the Idle Air Control Valve circuit may be

responsible. (Component testing shows

that it most likely is not the valve itself.)

Also, if the computer is deprived of its

“back up power supply,” some computers

will generate a false code for the Idle

Air Control Valve and kill the injector

End Wrench

14

End Wrench The

for cylinder #1. The pin location of this

power supply can be found in the Control

Unit Module I/0 Signal pages of the

appropriate Service Manual."

 

http://www.northursalia.com/techdocs/pdf/engine/emissions.pdf

 

 

So would this interruption to the battery back up power supply to the ecm cause a misfire or no pulse to the #1 injector, what is the best way to maybe circumvent this issue? 

[idosubaru]

I had a 99 sus and did same swap. 96 2.2 and all. I thought a 99 legacy sus or outback had a one year only ecu because of the phase 2 trans and phase 1 engine electronics

 

ah - i'm unsure of that 99 deal.

 

this thread suggests they're the same but they're not talking about 99's specifically.....but fairtax and bratman know their junk, maybe they'll see this.

[Fairtax4me]

Check voltage to the #1 injector. Need to know if its not working because the ECU is not commanding injection or if there's a wire issue.

 

The article above seems to indicate the problem will only occur at idle if the computer is cutting injection pulse. Does your misfire go away if you rev the engine up?

 

Have you checked to make sure all the electrical plugs on the bellhousing are tight? The main ECU ground connection is on the intake manifold, make sure that's clean and tight.

[tysn]

car fired up fine, after reading the article we came to the conclusion that the battery just needed to be replaced, we replaced the battery. ran great yesterday, started the car today after putting on some engine degreaser to clean the motor, now im back to square 1, as my luck would have it. the new engine is knocking something fearce , i think i may have pissed off the Subaru gods or something. 

[Fairtax4me]

That engine has hydraulic lash adjusters and they will clatter like the end of the world if they bleed out. Use a stethoscope and see if the noise is comiing from the heads. If it is, pull the valve covers and remove the rocker shaft assemblies. The feed port in the rocker shafts and tiny and easily plug up with RTV/or other crud, usually after someone has resealed the oil pump.

 

Blow the rocker shafts out with compressed air, pump up the lifters with fresh oil and re-install.

[tysn]

i took a stethescope to each head then to the oil pan, its really loud at the oil pan,

[Fairtax4me]

Any warranty on it?

[tysn]

no