Failed Emissions. Suggestions?
 

Hey,

Failed Colorado emissions.

HC GPM 5.1867 allowed: 1.5
CO GPM 29.9 allowed 15.00


Any suggested steps to pass?

How do you know if the CAT is dead?

Thanks for your thoughts and comments!!
Jim

Car:

'93 LE
Brain MS1
Delete MAF
Green top injectors (Celica 305's?)
BEGI S

Adding rather large log from the drive to the testing station.

Move to Florida. No emissions testing, no state income tax, no winter.

No winter pretty much killed FL for me. I need winter and mountains to be happy.

So you'd rather have mountains instead of racetracks? And smooth roads?

Clearly you haven't experienced the rush of skiing a 50% chute. Nothing else comes close.

Looks like you have too much acceleration enrichment. In your log file, I'm seeing drops to like 11:1 AFR with slight throttle movements even though your MAP is quite low. Look at 377.5 seconds for an example. I'll bet you can back off substantially on the enrichment. That enrichment will make the HC and CO values go off the charts.

Your idle is very rich too. Look at the stretch around 418 seconds.

Thanks, hornetball.
I'm going to work on dialing both of those in.
I'll post an updated log once I've changed things.

Still struggling... I don't understand how decel is supposed to work.
 

Still trying to get this tuned to pass emissions.

I've reduced fueling at idle, and actually ended up turning on EGO at idle because the car would run stoich one minute, but shut the car off and restart and it's pig rich.

I also reduced AE, and pushed up the sensitivity to reduce the rich spikes when I touched the throttle.

Now I'm trying to noodle through how the decel is supposed to work. If you look at 11750, MAP drops, and AFR goes rich.

So.... I clearly don't understand how the decel feature is supposed to work.

I welcome your ideas and comments!!

Two things:

1. It looks like, in general, you haven't tuned or need to retune the low MAP regions of your VE table. This would cover both the idle region and the "decel" region. I recommend that you get out and do some serious autotuning/VE analyze logging and try to get as much run time as you can in the low MAP region (idle, mid and high RPM with throttle nearly closed).

2. The feature that turns off fuel while coasting is called "overrun cutoff." There is a dialogue called "Over Run Fuel Cut" that you tune for this. While doing your autotuning/VE analyze logging, make sure you have this turned OFF so that your VE table is actually injecting fuel for the purpose of tuning. After tuning, turn this feature ON. The various controls are in the dialogue. From looking at your logs, you seem to have about 2 to 3 seconds of delay before overrun cutoff engages. You can easily reduce that to 1 second.

Not able to open your msq for some reason, otherwise I would be more specific with overun cutoff. I can tell you that my settings are (and these were the MSPNP defaults):

Fuel Cut When (all parameters AND'ed):
RPM > 2000
kPa < 20
TPS < 150ADC (note that this value completely depends upon your TPS calibration -- so don't use mine directly)
Coolant > 160F
After 1 second.

Thank Hornet.

I took it out and ran autotune on it prior to that log.

I'll take it out for another run. Do you disable AE for autotune?


Thanks,
Jim

Autotune and VE analyzer are both smart enough to recognize when AE enrichment is active and discounts those readings. It is also smart enough to recognize when overrun cutoff is active for the same reason.

The issue with leaving those features enabled is that it cuts down on the number of readings that can be used. I usually turn off overrun cutoff and leave AE alone while tuning. BTW, your original tune looked far enough out that you should make several tuning runs to get it back in shape. Don't stop until your AFR's are tracking your AFR table.

Note that the amount of AE you use should be based upon "just enough." Start with no AE and add just enough to get past any lean stumbles. With port fuel injected engines, you just don't need nearly as much as in the old Holley 4-bbl days.

W00t! Passed.

Quick question on overrun cut off. Is the TPS value the value at full open, full closed, or some place in the middle determined by...?

Thanks for your help guys!!

Jim

It should be just slightly above full-closed. Basically, it shuts off fuel to the engine while you are coasting in gear.

Good news on the pass. Plus, your car is probably running better. So in this case, the emissions testing was a positive.

Nice dude! Thanks for proving it can be done! I was skeptical I'd be able to pass Colorado emissions with a turbo + MS1. Can you post your .msq and also your emissions results?

Google High Plains Raceway and Miller Motorsports Park and then become jealous.

Here is the MSQ
 

Sorry for the slow reply on this.

Here's what I did. Based on some other threads on passing emissions, I pull 5% timing across the board below 100kpa. I pushed the AFR target table to 15 below 100kpa. Then I loaded the msq into megalog and had it to a veanalyze to rough it in, then took it out for an hour long autotune session. Finally, I got it nice and hot before the test.

Hope that helps.

Jim

Sweet thanks for that. Do you remember how close you were to the limits? Looks like my '96 will have to be cleaner than your '93, but not by much.

One other thing you can do is put a California state catalytic converter. Magnaflow makes one that is supposed to flow ok but meets the higher Cali emissions.

Here are my passing numbers:

HC gpm 1.0761 allowed: 1.500
CO gpm 4.4335 allowed: 15.000
CO2 gpm 347.9697
NOx gpm 0.2956 allowed: 3.5

Jim

I just passed with my turbo! So happy I don't have to worry about it anymore. Followed your procedure, disconnected the wastegate and set my targets for 14.7-15:1 and backed off the ignition timing a few degrees.

Check out all the codes it had! They said I passed CEL but they just didn't bother to look behind my ScanGauge lol.

I made a video too, just to show a little of what the IM240 test is like. Two-speed idle tests, what a joke.