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I've failed too many times to count now (7). I've tried everything that I know; first autotuning at afr 14.7 @ 15mph and 25mph using the gears the smog shop shifts into while on the rollers; then I did autotune while on the dyno, etc. I still can't pass. High HC and Co. I'm running rich. If I could send my datalog (while on the dyno) to someone that has greater understanding, I would really appreciate it. Thanks.

What are you using to tune? WB O2? What kind? Has it been calibrated recently? Do you have O2 correction turned on?

Definitely can't rule out ignition advance. Can you post your table?

Post up your datalog and your timing table/msq. AFR can be correct and with poor timing you will have problems.

Also, what cat are you running?

I have not calibrated my 02 sensor ever. My wideband is an AEM 30-4100. In autotune, it does show cells changing when I am tuning. Cell resistance is set to "normal" and Maximum Cell Value Change: 50.0
Cat is a magnaflow...3 months old, maybe 500 miles on it so far. My smog shop told me that 15mph simulates driving up a fairly steep incline. I thought this was why I might be failing, as I was tuning on flat roads, but when I ran autotune on the dyno, it didn't seem to help at all.

charofire wrote:

Nowhere near enough ignition advance. You're more than ten degrees conservative most places. Which engine is this?

This is an e23 745i turbo engine. Correct me if I am wrong, but a retarded spark curve should equal less fuel, but im still rich on the smog test (high HC and Co). I have a feeling that my o2 sensor is working like a narrow band instead of a wideband.

charofire wrote:This is an e23 745i turbo engine. Correct me if I am wrong, but a retarded spark curve should equal less fuel, but im still rich on the smog test (high HC and Co). I have a feeling that my o2 sensor is working like a narrow band instead of a wideband.

Retarding timing doesn't "equal less fuel". Not sure where this comes from. You are way too conservative on your timing. You are giving up power, response, and combustion completeness as well as you probably have extremely high EGTs. I am actually surprised that you pass NOx. My timing table isn't neccessariliy the best ever, but it should give you an idea how retarded your actually is. With the CR of the 745 engine you will likely need even more than what I am running at 9:1. You need to rework timing then rework the AFR table.

If Autotune is constantly changing cells, you're doing something wrong. Make sure the motor is at full operating temperature before you start tuning. Coolant and oil need to be at operating temperature for best results, otherwise you start chasing your tail a bit when it comes to the tune.

That said, the big Magnaflow (to you got the big one, right?) catalytic converter really catalyzes well, I'm not sure why you're having trouble passing. I passed CT emissions with a non-perfect tune, but Cali smog rules are tighter.

Jeremy

Ineffective acceleration enrichment will mess with autotune as well.

Is your autotune set to easy? It will usually continually make adjustments, but your there when its only making 1 or two point changes, any more than that requires further tuning generally. I don't think AE can affect ve tuning in the newer stuff, it has gotten smarter.

Let me post you the first ignition table--you will see its very similar to what was just posed. I passed Nox at 15mph and 25, but my HC and CO were double the allowable amount. So here is my first try at the smog station with my normal timing map. Someone mentioned earlier re calibrating my wideband. Is there a chance my wideband is working as a narrow band? And yes, the car was fully warmed up--my smog guy always asks the same question since he said that makes a huge difference.

So HC CO looked better with the first map you posted?
I'm also using low timing in that area to keep it smooth.

Using timing map above that is not retarded, my HC at 15 was 133, while the limit is 106. At 25mph, my HC was 115, while the limit is 81. CO: @ 15mph, mine was 1.67%, limit is .7%; at 25mph, mine was 1.18% and limit is .57%. So that brings me back to my original question that I started with: how to lower my HC and CO, which as my smog shop says mans I am running rich. His machine shows 13.7% CO2 which he says is almost equivalent to my afr reading. Cars that pass have 14.6-14.8 CO2 according to him.

your newer timing map looks too advanced to me in the higher boost cells. i can only run about 11* at high boost or I get knock.
I've not had to tune for emissions thankfully, but if you can't lean it out any more,then you might consider cam timing.
I've found advancing the cam can wake up the bottom end power where your having problems.
good luck
marc

Brad D. wrote:

charofire wrote:This is an e23 745i turbo engine. Correct me if I am wrong, but a retarded spark curve should equal less fuel, but im still rich on the smog test (high HC and Co). I have a feeling that my o2 sensor is working like a narrow band instead of a wideband.

Retarding timing doesn't "equal less fuel". Not sure where this comes from. You are way too conservative on your timing. You are giving up power, response, and combustion completeness as well as you probably have extremely high EGTs. I am actually surprised that you pass NOx. My timing table isn't neccessariliy the best ever, but it should give you an idea how retarded your actually is. With the CR of the 745 engine you will likely need even more than what I am running at 9:1. You need to rework timing then rework the AFR table.

How does it idle at 25* mine is at 10*.

I'm actually running with a second table that gives me more resolution around idle. I just set it at 25 to make the primary table smooth. I am around 10-12 degrees at idle.

thanks for the idle input--strangely enough, it idles well. But back to the main problem: the smog station tests my car (1600 rpm in 2nd gear for 15mph and 1600 in 3rd gear for 25mph). at 1500 rpm, my o2 vs rpm graph showed .38. Is this voltage and if so, that seems to be in the narrow band range. I have a wideband sensor that at the same speed shows over a volt which is correct for the sideband range output. What is Megasquirt reporting when it says .38?

So it's getting better numbers with the first or second map?

G&T: My motor wouldn't even idle at 10*. Turn the timing up
and if you're vacuum gets stronger then I think your engine likes it that way.

The original timing gave me the smog number I mentioned in my last post, or the second timing curve that I posted is the one that gave better numbers, but still double the allowable amount for HC and Co.

If you're testing at 1600 RPM the first thing to do would be to set a bin for 1600 RPM so you can make exact adjustments. As it is now its interpolating between 1300 and 2000 RPM. Get rid of 500 RPM, move 700 over, set the next one at 1100 and the one after that to 1600.

Try the following advance angles at 1600 RPM:
100 -28
80 -31
60 -34
50 -36
40 -38
30 -30

Isn't idle timing set elsewhere? I know it was on mine, but firmware and hardwares have changed a bit since I was messing with it.

I think something else wonky is going on with your wideband o2 sensor input. You should be able to display AFR, not o2 as shown in your logger screenshot, and it definitely shouldn't be reading anything close 0.3xx. What output from your wideband are you using and how is that output calibrated? Also, you have to do the same setup within MS so it knows what to do with the input. I have a feeling you autotuned with some sketchy data being sent from the WB.

Brad, can you tell me where to set the input? I don't remember.

I sent my MSG to DIYautotune and they looked at it for me. They said my EGO controls, specifically my "active above Map" setting was wrong. It was 90. They recommended 20.

What else do you all have for EGO settings Active Above Map and Active Below Map?

Same thing.
Active about 20.
Active below 290kpa (boost cut).

That's good you changed it. the o2 correction will help you allot.