dead ECU? - No check engine light when key is 'ON'

[w1kk3d]

You know how when you turn the key to 'ON' and all the lights come on/go off as usual... well, my Check Engine light doesn't come on AT ALL during this time (or at all).

I can start the car, but it will die within a second or two.
I can keep it running (crappily) by holding the rpm's at 1500.

The only thing I've done is uninstall my S-AFC, and a turbo swap (back to stock) at the same time.

I triple checked the wiring, everything is taped up, blue/yellow airflow wire connected again, etc.

I've gone over everything a million times, no leaks, everything is plugged in and hooked up, no blown fuses.

Car is now stock except for a walbro 190 that was installed last year.

What's going on?

 

[TwoLiterLaser]

You need to hook up a recirc. tube since you took off that S-AFC.

 

[w1kk3d]

You need to hook up a recirc. tube since you took off that S-AFC.

WTF It was never off in the first place, I'm not a atmosphere venting noob.

 

[TwoLiterLaser]

Okay dumbshit, why the #### does that picture in your profile show a BOV with no recirc? Noob that bi***.

 

[w1kk3d]

Okay dumbshit, why the #### does that picture in your profile show a BOV with no recirc? Noob that bi***.

Because it's from 2yrs ago... not 2 days ago when I returned it back to stock.

And besides the fact that automatics can run just fine without a dump tube as long as the intake is capped off.

 

[TwoLiterLaser]

I see. My apologies for jumping your shit. Automatics will still not idle correctly, and anytime your foot comes off the pedal it will go pig rich.

As far as the original problem, I doubt it is the ecu, but something to do with the S-AFC.

 

[w1kk3d]

I see. My apologies for jumping your shit. Automatics will still not idle correctly, and anytime your foot comes off the pedal it will go pig rich.

As far as the original problem, I doubt it is the ecu, but something to do with the S-AFC.

Trust me, it idled flawlessly
But yes, it did run alot richer from the unmetered air.

I untaped & checked/retaped every single wire that was used for the S-AFC, I've installed/uninstalled one more than once.
There's only 8 wires to solder in, so there really isn't much to uninstalling. If you wanted to do it sloppy you could just snip the 8 wires, and re-connect the blue/yellow a/f wire.

So my ECU is basically stock again, except for the butt splice holding the a/f wire together, and it's on there good, I pulled nice & tight on each side.
So... I dunno, I'm going to borrow an ECU and swap it in.

 

[chuckg]

You need to hook up a recirc. tube since you took off that S-AFC.

I may be wrong... but an S-AFC wont compensate for a vented bov will it?? I thought a translator and a new maf was the only route.

 

[w1kk3d]

I may be wrong... but an S-AFC wont compensate for a vented bov will it?? I thought a translator and a new maf was the only route.

Short answer, no, the s-afc will not.
rar.... this isn't about venting, go find the other 5,000,000 threads on the subject.

 

[steve]

You know how when you turn the key to 'ON' and all the lights come on/go off as usual... well, my Check Engine light doesn't come on AT ALL during this time (or at all).

I can start the car, but it will die within a second or two.
I can keep it running (crappily) by holding the rpm's at 1500.

Your light may be out since the car isn't going to start al all if the ECU is dead.

Did you pressure test after reinstalling the turbo?
What does your datalogger tell you about airflow?

Steve

 

[w1kk3d]

When you were undoing your s-afc and etc's, you kept the battery unplugged right?

Yes.

Your light may be out since the car isn't going to start al all if the ECU is dead.

Did you pressure test after reinstalling the turbo?
What does your datalogger tell you about airflow?

Steve

I didn't do a compression test because the battery isn't really at full power and would give false lower readings right?

Can't measure the airflow because it doesn't run long enough to get a reading (1-2seconds of lumpy half-dead idle)

 

[steve]

Pressure test not compression test. Most often called a boost leak test.

Steve

 

[w1kk3d]

oh ... no, I didn't. The car would still start even if there were vac leaks.
My brothers car had half the emissions hoses off and it still started up/ran like ass, but it still idled and wouldn't die.

I already thought of that too... checked every possible hose/stock ic pipe/intake, etc, everything is hooked up/clamped, MAS plugged in.

I read that the firing order for the 95-96's is different?
The 97-99's use the 1g order, but I can't seem to find what order it should be in.
I did swap plug wires, and have them 4-1-2-3.

 

[TwoLiterLaser]

I may be wrong... but an S-AFC wont compensate for a vented bov will it?? I thought a translator and a new maf was the only route.

Yes it will. Go here:

http://www.alamomotorsports.com/apexi/safc.htmo

 

[steve]

Yes it will. Go here:

What exactly are we looking for?
A stock SAFC doesn't do deceleration air comp with a Karman MAF. Maybe the Neo does but the others don't.

Steve

 

[w1kk3d]

It was my CPS, it was cracked/broken nearly in half.

As seen in #3 here:

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