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Old 06-15-2010, 08:50 PM   #1
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Default Car sputtering and spitting in boost, datalogs look normal?

I can't get going into boost; soon as it goes above ambient pressure it just starts to **** itself. My datalogs don't show AFRs, does that mean my LC-1 is shitting itself and it's not getting signal? It shows in tunerstudioms though, it just doesn't include it in the datalog. In tunerstudioms though, it shows running nearly 11:1.. at idle.

I'll post my datalogs; anyone see anything wrong with them?
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Old 06-15-2010, 09:48 PM   #2
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What plugs, what gap and how much boost?
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Old 06-15-2010, 09:59 PM   #3
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Stock plugs and wires (NGK) and 7 pounds. But I doubt it's that; it was running fine. Turbo blown. Replaced turbo. Now this. And the boost level is irrelevant since it sputters so bad that it can't really gain any boost.
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Old 06-15-2010, 10:44 PM   #4
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Could an exhaust leak before the WBO2 cause this? I highly doubt it since it does fine till boost, but it seems like it's worth asking.
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Old 06-15-2010, 11:04 PM   #5
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I too say change your plugs and wires. It will cost you $20 to eliminate that as the culprit. If you look at the threads here you'll see the same symptoms cured by that fix. Gap lower too.
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Old 06-15-2010, 11:25 PM   #6
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I'll try that, but they were replaced about 1k miles ago.

So I just went out and test drove again, I learned something. If I keep it floored through the bumpiness it eventually takes off like it should; it almost seems transition dependent or rpm dependent, haven't decided which. Took a better datalog, I'll get it up in a second.
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Old 06-15-2010, 11:34 PM   #7
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Ok, datalogs attached. I'm going down to 0.8AFR (!!!) and 250-some % duty cycle...

EDIT3: That 0.8 wasn't AFRs, they're normal, so this is a spark problem isn't it?

WTF?

EDIT: Ok, looks like MAT is no longer working, could this cause what's happening to me? Like stuck in warmup mode or something?

EDIT2: So could this be caused by having no open loop mode? I just set mine to turn on as soon as it goes above ambient pressure

EDIT4: OK, overboost protection was set to -0.6psi... This could be it, can't wait to testdrive tomorrow. How does overboost protection work? Like I said it hit that, stumbles, and if I keep at it for long enough it'll eventually go. Sound like it's hitting overboost?
EDIT5: Actually, that wouldn't explain the 250% duty cycles yet normal AFRs...
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Last edited by rider384; 06-16-2010 at 01:42 AM.
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Old 06-16-2010, 02:33 AM   #8
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Whooah, one thing at a time. Yes, fix the ait signal first. If MS thinks it's -40 ait, it will dump a **** ton of fuel in it. My connector vibrated loose on mine and it did the same thing, read -40. I barely made it home(10 miles) and had to change the plugs the next day because they were fouled.
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Old 06-16-2010, 02:36 AM   #9
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Forgive the noob question, but where is the MAT sensor? Hmm, that would also explain the duty cycles and richness all over aswell.
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Old 06-16-2010, 02:41 AM   #10
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Where did you put it? It should be in the intake pipe or the intake manifold somewhere. I can't see it from here.LOL
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Old 06-16-2010, 02:45 AM   #11
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Quote:
Originally Posted by lordrigamus View Post
Where did you put it? It should be in the intake pipe or the intake manifold somewhere.
Oh, nevermind, I misunderstood. It's late at night, what can I say

I'll double check, one of the wires fell out and I put it back into a random one hoping it was right

EDIT: Ok, IAT was hooked up wrong, gonna go try again tomorrow. Hopefully it'll cure it, but doubtful since it felt like a park probrem.

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Old 06-16-2010, 02:35 PM   #12
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Took some datalogs this morning. Doing all of that last night fixed my messed up AFRs and it does enter boost now, but I get some sort of weird stumble. You can see it in the datalogs; the TP is 100%, pressure is building, but the rpms don't go anywhere. AFRs are normal and duty cycles are normal aswell.
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Old 06-17-2010, 03:03 AM   #13
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What size injectors are you running? I'm seeing duty cycle spikes well over 85%. Are your injectors maxed out? 136.5% duty cycle is not normal.

Last edited by lordrigamus; 06-17-2010 at 03:26 AM.
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