Code 12 and 43 help!

[mike-tracy]

So I was doing a bit of work on my car today, and cleared my codes the proper way with the green and black connectors. I follow the procedures again to enter active code check, and after a few minutes of driving with the green plugs connected, the following codes appear.

12 (Abnormal signal emitted from starter switch) and
43 (??? Google search says Throttle Switch)

I took a vid so you can see if I'm possibly misreading this

http://www.youtube.com/watch?v=S6HsAWaVXHU

Car seems to run fine all the time - no fuel cut or any other wierdness. When warm, the boost gauge says -19 at idle. It's about -16 or so when cold. Boosts to ~6psi in the first couple gears, then right about 10psi for the last few gears.

Here's the setup:
1991 SS
Factory 5mt
full EJ20G/ heads from a 96 WRX and intake manifold from a 90 Legacy/Liberty RS
EJ22t wiring harness
TD04 from a US WRX, 90* silicone bend to intake, coffee cup, stock airbox
JECS N/A MAF
440cc graytop injectors
WRX Slanty TMIC
EJ20G "3B" ecu, not chipped. This is from an early 90s WRX Wagon Automatic, lol
Phyrram's patch harness with an SVX igniter and 2 regular igniters. This ECU and patch harness has been successfully run on 3 SS's, and doesn't throw the same codes, on one, and has no codes on the other.
Everything connected in a 100% stock configuration for an early ej20g

Lastly, the code 12 goes away when come to a stop and let it idle for a minute or two. Won't come back till I reset the codes and go back into active check (and drive for a couple minutes - then both come back).

Edit:
Rob has some good info here:
http://forums.nasioc.com/forums/showthr ... ht=code+43

Does anyone else running an ej20g ecu, chipped or not, get code 43?

[mike-tracy]

Additionally, when I have the key in ACC, it blinks 45, 24, 31 in that order. That's with no plugs connected.

[Legacy777]

That's interesting you're getting those codes, and that you're getting codes with nothing plugged in.

I'm not sure what to tell you. Did you get those codes prior to running the EJ20G ECU?

[mike-tracy]

Hi Josh, I didn't check for codes I had with the ej22t ecu. The car ran so horribly that I swapped it out for the ej20g setup after about 5 minutes of run time. I'm sure the ej22t ecu would have ran better once it had learned the system, but the ej20g ecu ran great from the first startup.

Other than the codes, it idles and runs beautifully now. Gets about 19-20mpg mixed driving but that's an issue for another thread.

I'm going to reset the ecu by unplugging the battery and let it sit over night.

[Legacy777]

Ok, well let us know how it goes.

[mike-tracy]

Well a little update - I did some work in the engine bay, and disconnected the battery overnight. So with the now reset ecu, only code 43 came back! Damn throttle switch.

[Alphius]

Is the throttle switch/TPS adjusted correctly?

[mike-tracy]

Prob not - I've never messed with it. If you have some free time I'd still like to come over to pick your brain.

[Alphius]

Sure. Let me know what you want to do.

[wtdash]

Mike,
Looked into this, too. The 43 (not a USDM Legacy ECU code, per Legacy Central's ECU page - HERE - which you already knew) appears to be specific to EJ20's.

Check this SITE (copying to my EJ20G thread).

and this THREAD for more info....

I don't think (yet) it's TPS, but I think I read somewhere that JDM had a throttle switch....yep...found it in your LINK above:
Per Rob: "it's for the throttle pedal switch found only on JDM models"

When I still had my Legacy and it had the unchipped 'Z4' EJ20G EcU, I didn't have a 43 code. I wonder if your '3B' is a JDM ECU? Per Rob's post , if you get the Rob Tune, he can turn it off, too.

I checked the EJ20 pinouts on '96 WRX and didn't see anything about a 'throttle switch'.

Td

[mike-tracy]

I reset the codes again using the black and green plug method, and now no codes show. But now I'm limited to 5-psi!

[wtdash]

How far did you drive?

It can take a couple 'pulls' to bring it back.....(yeah, you know this, but I'm going to state the obvious anyway).

Td

[mike-tracy]

Reset the ecu last night, and drove it ~30 mi to work this morning, and all was well. It was just on the way home that I noticed the lack of power... I'm pretty sure this is a failing sensor or a leaking hose somewhere.

[Thesubielover]

Once or twice my engine light came on too and I noticed less power. Oddly enough, I just had to restart the car and it would go off; and back to normal power.

[Alphius]

The ECU limiting boost to wastegate pressure happens because of three things:
1. Excessive knock (permanent lowering, cannot be fixed by restart)
2. Overboost (can be fixed by restart, does not throw a code)
3. Problem with boost control circuitry or MAP sensor (can be fixed by restart if intermittent, might show a code or light the CEL)

Mike- Check your knock retard tables and Octane Factor values if you have some sort of scanning software available to you.