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Brewtus
Posted on Wednesday, September 21, 2005 - 07:55 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I just installed my PC III with the optional O2 sensor. My air fuel guage reads fine at idle when cold, but after about a 20 minute ride, my guage indicates very rich. I noticed that the idle is steady, but not as "lopey" once it's warmed up. I am running a zero map with a 1% bias on the O2. Any ideas why this is happening? I didn't have this problem with the TFI box.
Thanks.
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Buellistic
Posted on Wednesday, September 21, 2005 - 08:28 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Is it over 12 to one ???

In BUELLing
LaFayette
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Brewtus
Posted on Wednesday, September 21, 2005 - 08:31 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Haven't checked, but it will make you're eyes water in the shed.
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M1combat
Posted on Thursday, September 22, 2005 - 11:31 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I assume you've ridden it to settle the AFV.

Try removing the closed loop bias setting. I don't know that it's actually 1%...
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Scitz
Posted on Friday, September 23, 2005 - 11:14 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

How are you adjusting the closed loop bias? Does anyone know when mapping what pos and neg numbers in the map transfer to richer and leaner?
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Cruisin
Posted on Friday, September 23, 2005 - 12:11 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

The PCIII gives you an O2 setting option of 0 (no change), 1 (richer tries for 13.5:1 I believe), and 2 (for turbo/nos bikes). The PCIII takes the O2 and plays with the fuel ratio in the closed loop section to achieve the richer output.

As far as the numbers in the table, aren't they a percentage? If you put in a 3 it adds 3% more of the current fuel output. A negative number does the opposite (removes 3%). 0 is no change. The suggestion is to leave the closed loop area alone and let the PCIII do it's thing, and tune the rest accordingly.

Someone (I forget the screen name) who is familiar with tuning the Buells mentioned that the closed loop portion is 0-3500rpm and up to 80% throttle.
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M1combat
Posted on Friday, September 23, 2005 - 01:12 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I'm not sure if it was up to 80%...

Look here...

http://www.powercommander.com/man_chp4_pg17.shtml

They say there that you can tune "the Box" if you have the optional O2. I don't believe them. I leave the box alone. I also increase "The Box" to 4500 as I think the XB ECM stays in closed loop to there unless you've got the throttle open past 40%.

Also... "fade" the tuning in. If you slowly roll on the throttle you'll get an abrupt power difference at the edges of the box. You need to fade the tuning in over the two rows/colums that are around the box. Basically, If you shoot for a 13.5:1 mix and the stock setup is at 15:1... Shoot for ~14.7:1 in the first ring around the box, then shoot for ~14.2:1 in the second ring and finally 13.5:1 in the third and subsequent rings in the map. This "should" give you a nice smooth transition from closed to open loop. I didn't realize this myself until after I had the bike tuned for two pipes... I'm working on it manually now.

Also... When you install the PCIII, I think it's best to set the enrichment to "1" and run it for a while with an otherwise "zero" map to ensure that the AFV has settled with the "1" enrichment. Then tune.

I don't think the entire situation is worth the time if you don't have the optional O2. Also, you may need a different map for summer/winter depending on the temperature shift in your area. I say tune it in the spring/fall and call it good though....
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M1combat
Posted on Friday, September 23, 2005 - 01:14 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Also... I don't think the "1" enrichment tries for any specific ratio. I think it just adds a percentage of fuel and hopes.
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Brewtus
Posted on Saturday, September 24, 2005 - 11:23 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

M1,
I settled the AFV as per you're instructions in another thread. I removed the 1% bias and the guage still reads rich when it gets warm. I think I'm going to try another O2 sensor and see if that helps.
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M1combat
Posted on Monday, September 26, 2005 - 01:10 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Do you have the optional PC O2 or just a standard O2?

I strongly recommend the PCO2 or a comparable one. I've been told it helps tremendously, but personally I've only used the PC WITH the O2, so I don't have any personal exp.
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Scitz
Posted on Monday, September 26, 2005 - 02:51 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

So in the non closed loop area of the map if I add the number 3, for 3% will it add 3% more fuel or air? If I'm running rich above 4000 rpm will I want to use a positive or negative number in the fuel map to lean the mixture? I hate that the PowerCommander website and documentation isn't very descriptive in creating maps, or I just haven't been able to find the info, they just say to check with one of their tuning centers.
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Brewtus
Posted on Monday, September 26, 2005 - 02:52 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I have the optional PC O2. I have another one on hand from a newer Ford that I am going to try.
Have you been to the Technoresearch site lately?
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M1combat
Posted on Monday, September 26, 2005 - 04:34 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

If you put in a positive 3, it will add 3% fuel.

If you're rich above 4000, you would put in a negative number. Be VERY careful with negative numbers.

Too rich fouls plugs.

Too lean burns holes in pistons.

One more thing... If you put -15% on your zero throttle column from 2000-6000 RPM you can get rid of popping on deceleration. Do that at your own risk. I run -35% with my Force pipe and it seems to be OK. I'm running -35% from 2K to 5500 now, but when I get around to it I'll be taking it to -25% from 3500-5500. Only because I figure having the most fuel w/o popping on decel is probably the safest thing so if I can add a little fuel and still not pop, I'm good.
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Scitz
Posted on Monday, September 26, 2005 - 05:12 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Thanks, M1combat. That's the type of info I was looking for. I put my bike on the dyno and it's running rich after 4000rpm at a steady ratio. I'll start with -5 and take small steps from there and then try to dyno it again. It's also popping on deceleration so I'll start small in the zero column and test it out.
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M1combat
Posted on Monday, September 26, 2005 - 06:00 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I would start at about -10% on the zero TP column. You'll probably end up about -15-20% from 2500-4000 and about 6-8% less (-11-16%) above that.

Just so you know, I also went to +25% in the zero column and it made the problem a LOT worse so I'm pretty sure it's a rich condition on decel that caused MY popping...

If you spend some time tuning that you can get a nice sounding gurgle out of it : ).

(Message edited by m1combat on September 26, 2005)
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Indy_bueller
Posted on Friday, November 04, 2005 - 07:35 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I've been talking to some local shops about the PCIII and they say that even if you get it tuned it still wont be good because the PCIII is tuned for the air temp, humidity, etc of THAT DAY. Whereas the ECM constantly adjusts depending on conditions. Have any of you been able to get one to work consistantly?
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M1combat
Posted on Monday, November 07, 2005 - 02:25 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

The ECM's adjustment ability is still able to compensate for changes, but it does "slightly" change the map needed. I've heard it's useful to get a "summer" and "Winter" map. My summer maps seem to work alright so far, but it does die once every morning about 10-20 seconds into my two minute warm up.
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Buelldyno_guy
Posted on Friday, December 30, 2005 - 08:06 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I was the person who posted that if you can find a DynoJet Tuning Center that has "Tuning Link" which is dyno/PC software the process is easy, but takes a few hours. PC3's have always worked well if you know how to tune them. To do that you need to know what the ECM is trying to do to the AFV in "Closed Loop and Open Loop. We are a DJ Tuning Center and while at a class at DJ where one of the Tech's was a S3 rider, we worked on a MAP for my S3 using a process he had developed. So I have been using a PC3 for several years now and have refined his process on our dyno.

On Tubers: 1st Zero the TPS then reset the AFV and disconnect the 02 sensor and put 0 (zero) in the Closed loop area of the MAP. Tune all cells outside the CL to a value of 13.5 to 1. Use a +1 bias to the 02 sensor and reconnect the sensor and go ride.

On XB's the process is the same but the "Closed Loop" is not defined in the DJ PC Software because they quit making Buell PCs before the XB's came out. So the CL is just off idle approx. 2% tp thru 60% tp 1500 thru 3500 RPM. Again have the tuning center use "Tuning Link" to MAP all open loop cells to 13.5 .

A couple of hints watch the temp DJ says tuning must be accomplished between 265 and 280 deg F This is why it takes so long. At the high TP and RPM ranges you can go from 265 to 300+ while doing just two or three cells in your MAP. This could be why it is rich in some places in OL. Above 300 the ECM starts to add fuel to cool things off while you might be trying to lean it out. ... So Again Watch the Temp. I have never had it not work. ... Terry
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Blake
Posted on Friday, December 30, 2005 - 09:15 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

That's really great info Terry. Thanks!
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