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Old 01-12-2010, 01:50 AM   #1
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Default Why is my AFR so noisy?

Ths is a '95 with MS1 and an LC-1. I can't get a smooth AFR like many of the logs I've seen. I've messed with the grounds several times and tried different locations, leading me all to the same sort of logs like this one.

The only thing that I haven't been successful at is getting LM Programmer to stay configured to 0-5 10-20:1 like everyone else. I can connect *sometimes* to LM Programmer, then when I hit "Program" and play with the tabs, it resets to default settings. I've read one other thread on this problem, but I'm not successful at getting a fix. TS and my analog AFR gauge reads the same AFR though I'm confused by this because TS is set to 0-5 10-20:1 so I'm thinking it's not a configuration problem?


Here's a quick log at idle. The AFR fluctuated from 13.8-14.9 : /.
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File Type: msq 2009-12-29_01.48.41.msq (32.2 KB, 69 views)
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Old 01-12-2010, 02:03 AM   #2
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Yea I had the same exact problems with my LC-1 then found out it was a bad sensor that was causing some b.s. short, So I switched to the AEM and will not turn back.
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Old 01-12-2010, 02:29 AM   #3
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I'm not happy being on my third USB/Serial cable also. I'm already reading the AEM install instructions and it looks way simple and less finicky.
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Old 01-12-2010, 02:39 AM   #4
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Describe to me in vivid, vivid detail how your LC-1 is grounded.
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Old 01-12-2010, 02:53 AM   #5
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I extended the wires with 18 gauge wires and I had each wire soldered into it's own lug and grounded it where the throttle body attaches to the intake manifold (4 bolts here). I've also tried the two bolts holding down the throttle cable. These were both suggested by Hustler, but it didn't work.

Right now I have all wires soldered into a single lug (best config. from the manual) into that ground to the right/under the throttle body.
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Old 01-12-2010, 02:53 AM   #6
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I extended the wires with 18 gauge wires and I had each wire soldered into it's own lug and grounded it where the throttle body attaches to the intake manifold (4 bolts here). I've also tried the two bolts holding down the throttle cable. These were both suggested by Hustler, but it didn't work.

Right now I have all wires soldered into a single lug (best config. from the manual) into that ground to the right/under the throttle body.
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Old 01-12-2010, 04:36 AM   #7
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On the 30kPa row, the first cell (800rpm) is 39 and the next (1200rpm) is 46, while the one below the 46 is 40. You won't get a steady afr like that.

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Old 01-12-2010, 08:52 AM   #8
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Not to doubt Hustler but those don't sound like great grounds, aluminum isn't the best conductor. Try the body somewhere, see what happens.
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Old 01-12-2010, 09:54 AM   #9
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any reason your map sensor is brokenz?
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Old 01-12-2010, 10:01 AM   #10
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He's idling, it's only changing 2kpa.
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Old 01-12-2010, 10:06 AM   #11
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As far as the AFRs, you should try setting the VE table so all the surrounding cells are the same and see if it stays the same. If it does, then there's probably something wrong with the sensor like p51 said.

Also, you say the MS and LC-1 give the same readings, so I'm assuming they're grounded to the same spot? If not, they should be.
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Old 01-12-2010, 10:13 AM   #12
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Your LC1 programming issue mimics one of the problems I was having before sending it to Innovate. They recommended to me to try reflashing the firmware before sending it in for service. In my case, reflashing did not do anything, but it's worth a try.

The range of oscillation in a/f you're experiencing at idle isn't that great. It's less than what the factory computer would go through in closed loop idle. It would get smoother if you hand tune for 14:1 and set your bottom-left 4 VE table cells much tighter (have very small changes between the numbers in those cells). 7 points is too large of a difference there and may cause lean-rich oscillations.

Your screen cap is scaled funny and you show AFR twice. I'd have rather seen TPS instead of AFR again. I can't tell what's up with the spikes in MAP.
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Old 01-12-2010, 12:19 PM   #13
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Quote:
Originally Posted by Reverant View Post
On the 30kPa row, the first cell (800rpm) is 39 and the next (1200rpm) is 46, while the one below the 46 is 40. You won't get a steady afr like that.
Jim
Yeah, it as when I had idle issues and was idling in that cell. I'll change it.

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Originally Posted by TrickerZ View Post
As far as the AFRs, you should try setting the VE table so all the surrounding cells are the same and see if it stays the same. If it does, then there's probably something wrong with the sensor like p51 said.

Also, you say the MS and LC-1 give the same readings, so I'm assuming they're grounded to the same spot? If not, they should be.
I think I've done this, but I'll try it again too.

Quote:
Originally Posted by Ben View Post
Your LC1 programming issue mimics one of the problems I was having before sending it to Innovate. They recommended to me to try reflashing the firmware before sending it in for service. In my case, reflashing did not do anything, but it's worth a try.

The range of oscillation in a/f you're experiencing at idle isn't that great. It's less than what the factory computer would go through in closed loop idle. It would get smoother if you hand tune for 14:1 and set your bottom-left 4 VE table cells much tighter (have very small changes between the numbers in those cells). 7 points is too large of a difference there and may cause lean-rich oscillations.

Your screen cap is scaled funny and you show AFR twice. I'd have rather seen TPS instead of AFR again. I can't tell what's up with the spikes in MAP.
Some of the time when I try to hook up the LC-1 to my laptop, my AFR in TS and my AFR gauge actually gets suck until I cycle the ignition again. I'll try to see if I can connect again in a bit. It's just a bit discouraging when I see AFR logs like this one.

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Old 01-12-2010, 12:28 PM   #14
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just rubbing it in...
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Old 01-12-2010, 01:11 PM   #15
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AFR line looks fine to me. It loks so jagged because the 'high' is a mere 14.8 and the low is 13.9

Try driing around aswell so you get a full range of AFR's that in it's self will smooth the graph out considerably.

Also echo Ben and Jim, keep the idle bins similar/exactly the same.
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Old 01-12-2010, 02:15 PM   #16
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Alright alright. This looks much better. I guess I've been jaded by really even looking AFR like Braineack's. Thank you all for the fast inputs! I'll get to tweaking it later tonight.

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Old 01-12-2010, 02:16 PM   #17
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Quote:
Originally Posted by Ben View Post
Your LC1 programming issue mimics one of the problems I was having before sending it to Innovate. They recommended to me to try reflashing the firmware before sending it in for service. In my case, reflashing did not do anything, but it's worth a try.
On the programming issue, I also found that the values didn't like to "stick" when I programmed them as 10:1 or 20:1 AFR. So I did the math and input the numbers in LM Programmer as lambda values instead of AFR and now it works perfectly, first time every time.
It seems the software no habla AFR muy bien.

EDIT: Woot! 500th post! I am senior! LOL
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Old 01-12-2010, 02:30 PM   #18
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I love the calibrate wide band feature in MSII.
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Old 01-12-2010, 02:44 PM   #19
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Looks like you rescaled the table a little. What size are your injectors?
A little rich at and coming off idle will ride nicely. Lean spots will surge or buck. The fuel economy penalty for running a tad rich at light load will be very small.

It also looks like you allow autotune to affect changes in the idle area. I prefer to tune idle by hand and then restrict the autotune to not make changes in light load by setting up the filter on the VE analyze dialog box.
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Old 01-12-2010, 02:46 PM   #20
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Quote:
Originally Posted by ScottFW View Post
On the programming issue, I also found that the values didn't like to "stick" when I programmed them as 10:1 or 20:1 AFR. So I did the math and input the numbers in LM Programmer as lambda values instead of AFR and now it works perfectly, first time every time.
It seems the software no habla AFR muy bien.

EDIT: Woot! 500th post! I am senior! LOL
Mine always walked by some extremely minimal amount, like .01:1. I assumed it was just rounding error from being converted back to lamda or something. Wasn't a big deal.

Really though, lambda values are so much simpler to deal with than a/f. I don't know why somebody decided that we needed to add an extra level of complexity. But it is what it is.
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