VERY rich on startup. stumbling

[Father Time]

this problem poped up about 3 days ago. when i start the car it stumbles bad or dies. then i have to turn it over forever till it stumbles and starts. the wideband cant read anything yet but i can smell the raw fuel. any ideas?

370cc
safc
ka-t
stock maf

thanks

[Father Time]

bmp................

[Father Time]

i noticed when i give it more gas and hold it around 2k rpm it will start with less stumbling ( but still stumble ). i get a lot of smoke though. smells like raw fuel.

[NemeGuero]

Pull some injector duty off that SAFC and see if that fixes it. Sounds like your IDT is wrong.

[Father Time]

thanks, could you explain a little more for me?

[NemeGuero]

You run rich because the engine is cold. (it uses a different fuel mapping) If you pull back some of your fuel on your SAFC, it should fix HOW rich you're running (eliminate the stumble)

[Father Time]

that was the first thing i tried. doesnt matter how much i pull back. still starts bad.
its so rich i smoke.

[Father Time]

anyone? im sure this has happend before

[HalveBlue]

Check your timing and plugs.

If you smell fuel it means that your motor isn't combusting the air/fuel mixture properly.

Also, check your injectors.

[JohnC]

just for the sake of elimination, unplug your narrow band lambda and see
if it makes a difference. if it is still connected.

[Father Time]

Its not wanting to start at all now.

whats narrow band lambda? my O2 sensor?

[NemeGuero]

yes narrowband lambda is 02 sensor. Ditch the SAFC and see if she'll crank.

[Father Time]

Pulled the O2 and it still starts hard but i noticed my 2krpm studder went away. It used to go very lean at 2k for some reason.

If i pull the safc how will i run on 370's?

[JohnC]

you might be able to get away with it if the O2 is connected (if it works properly). It might take it a short while to make the car idle.

[BigVinnie]

If i pull the safc how will i run on 370's?

Larger injectors will still dump more fuel than lets say if you had the 270's. Duty cycle will just remain more consistent with stock ecu settings. You should be fine if infact you are still using the stock maf. Alot of people still use the stock ecu without an SAFC as long as they have tghe stock MAF with it as well.
Just make shure that timing at the distributor is retarded to about 12BTDC. Any way to prevent detonation would be best.
Sounds as if your situation could be that your engine is running piss rich for one of three reasons......
Faulty vacuum line
Bad O2 sensor
leaky manifold pressure

[Bay_Area_sr20det]

simaler thing happend to me, might try checking all you intercooler piping.

[AceInHole]

1. Is your MAF plugged in.
2. Is your S-AFC installed correctly.
3. Are your S-AFC "IN" and "OUT" settings correct.
4. Is your ignition (distributor) timed correctly.

[yokotas13]

do this also
corrected my idling issues
Write up by Hugh:

Start when the car is cold. (after an overnight rest)

Turn key on, go to decel air settings.

Set throttle to 1%.

Set NE1 to about 4.

Set NE2 to about 5.

Start car.

Adjust NE1 until you get a smooth idle while the engine is still cold. Now start turning it down as low as possible while still maintaining a good idle.

If the car starts sputtering and getting rough, you just went too low. Turn it back up very slowly until it smooths out. You want to leave NE1 on the lowest possible point with a good idle.

Now set NE2 to be about 1 higher than NE1.

This formula shoudl eliminate any stalling or popping from the BOV being open.



Theory: Throttle setting tells the SAFC whenever the pedal is depressed less than 1%, the SAFC should control fuel and ignore everything else (including the MAF)

NE1 is the first RPM point you have selected in your NE Point settings. I put mine at 1000 rpm. I set NE2 at 3000, then NE3 at 4000, and so on in 1000 increments. Setting NE1 down at 1000 gives you the ability to control fuel at idle really well. Besides, you probably don't need to adjust anything between 1000 and 3000. (turbo spools after that, right?)

Setting the air flow percentage at NE1 is basically telling the SAFC a number to use whenever it reaches that RPM and less than the throttle setting. So, as the throttle is let off, the SAFC looks at the NE1 and NE2 points. As RPM rolls back, there is going to be a reduction in air into the engine, yet the MAF has already seen it. The stock ECU is attempting to send the fuel for that air that is now missing... hence your stalling and backfiring. The SAFC catches that signal, ignores it, then tells the ECU exactly how much air flow you have according to your DEC AIR settings at those RPM points. Get it?

RPM comes down, hits NE2, SAFC sees 10%. It tells the ECU it needs 5%. (because you picked that number.) Now the RPM won't dive so hard like it was. It reaches NE1, SAFC sees 6%, you told it 4% and it tells the computer only 4%. The idle sets steadily down to where its supposed to and everybody is happy.

The SAFC is all about tricking the ECU into doing what you want it to.