An update on mileage saga and PCV

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Eric L

Not that kind of a doctor
Joined
Sep 21, 2010
Messages
749
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Location
Boyds, MD
Bike:

2009, 8000 miles

stock and v stream windshield

occasional topbox use

PCV with custom dyno map came on used bike, O2 sensor is disconnected, air filter does not have mice living in it.

noticed right away that the computer on bike and the actual mileage had nothing to do with each other. This is because of the PCV. Previous owner said he got 40mpg... uh no. He's wrong. Bike with all stock and a sedate back road commute was getting 30-32 mpg. Screen, top box influenced it only a little. I guess I wasn't going that fast :). Even babying it got me no more than 32mpg. Some trips on the highway, down to skyline, and I managed to eek out about 34mpg.

Traded the custom map for the smoothness map translated over from the PCIII. This helped. Mileage with highway 50%/backroads 50% moved up to 36mpg-38mpg. The map that was on the bike was slightly leaner on the left side of the map but very rich on the right side (the highway cruising side). The smoothness map felt a little lean actually at highway speeds to my uneducated ***. But the low end felt essentially the same. After a few tanks of 35-37mpg, I loaded the map from the power commander guys. Its leaner than the smoothness map on the left but a little richer on the highway side. I ran 500 miles through that. I feel no difference in the low end, but to my (again uneducated) ***, the highway feels a little better. On the 350 mile Sunday ride I got 38mpg on twisty hilly route 50 west with a 25mph headwind and 46mpg doing 75mph all the way home on rt 68/rt 70 eastbound. OK, fine I had a tailwind on the way home. But I have NEVER even gotten 38mpg before, let alone 46mpg.

So things are better. 25% better mileage is a great thing with $4 a gallon gasoline prices. I still have the dreaded vibration between 4000-5000 rpm, but haven't done the TBS yet. Hopefully that will help.

 
Glad to see things improving, Eric. It might be interesting to unhook the PCV and plug the 02 sensor back in.... at least I'd be interested if that made a difference to response on your uneducated ***, 'cuz then I'd guess it was becoming educated!!

I agree a TBS should smooth things out a bit.

 
Glad to hear you're getting it sorted out. How many people actually mess with the ECU/EFI on the '08 and up Gen IIs? I've always felt mine ran perfectly bone stock. I'd recommend you try going back to a bone stock configuration and give it a try.

 
You USA guys have got a good deal on fuel, I know I'm over your way enjoying the Florida sun. I pay $9 per gallon in the UK.

I use the PCV with autotune. I get good mileage. The autotune gradually adjusted the trim, I have set the trim for no more than 5%.

BTW. I'm thinking of exporting a f150 lariat limited 6.2ltr, has anybody got the new model and what is their opinion, good and bad?

Andy

 
Just to give you another data point, my 06 essentially stock, always with all bags and Givi, and larger CBailey flip, gets me between 36MPG and 45MPG. That's generally pretty mixed riding, and I have a hard time keeping my wrist out of it so it's not 'MPG Optimized riding in any way'.

On Longer Rally type slab riding I can get 48, but the bike is generally more heavily loaded as well. I tend to cruise around 5-7 over the posted limit. On the east coast/midwest, that puts me in the 70-75MPH range with some runs at around ~80.

I've never ever really gotten to 50, but figure I could if I took the top case off and used a smaller windscreen but that's not going to happen.

Yes, a TBS should help you, as will grip puppies.

-MD

 
For sure I am planning (just for the edumacation) to reconnect the O2 sensor and load the base map and run a few tanks. It's been suggested on this forum before that I just yank the sucker out and sell it if I cant feel any benefit and the mileage is the same or better.

 
I run my PC3 with o2 connected and zero map on the left and Muzzy map above 20% throttle. I'm happy with it other than the slight flat spot around 4k rpm, but that's just how it is with headers.

 
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Perhaps I am still underedumacated, but (oversimplified), doesn't connecting the 02 sensor basically render the PC3 or PC5 ineffective? Of course, for a true test of stock, one should disconnect the PC and connect the 02.

https://www.fjrforum.com/forum//index.php?showtopic=117893&st=0&p=589862&hl="oxygen%20sensor"&fromsearch=1entry589862

https://www.fjrforum.com/forum//index.php?showtopic=123938&st=0&p=671217&hl="oxygen%20sensor"&fromsearch=1entry671217
That is my understanding too. It will fight with the PC III/V.

 
Perhaps I am still underedumacated, but (oversimplified), doesn't connecting the 02 sensor basically render the PC3 or PC5 ineffective? Of course, for a true test of stock, one should disconnect the PC and connect the 02.

I run my PC3 with o2 connected and zero map on the left and Muzzy map above 20% throttle. I'm happy with it other than the slight flat spot around 4k rpm, but that's just how it is with headers.

See above. You are negating the effects of the PCIII by having your O2 sensor connected. Don't believe us? Call Dynojet and let them tell you to disconnect the O2 sensor.

 
I only wanted the tuning of the PC3 for the near WOT stuff, and from what information I have gathered on here and elsewhere, the O2 sensor is not going to play a role in those situations. Cruising and other partial throttle applications my bike runs great stock.

If I am wrong about the system operating in open loop during 60-100% throttle, someone please tell me.

When it was/is 20-40F here earlier this spring, I noticed the bike ran a little better with the O2 sensor connected. FWIW, I used the PC3 the last year with the o2 disconnected per the directions, and I don't notice any difference either way to be honest, other than the said low temps.

 
Thanks for the updates. Please keep them coming. I've noticed almost identical mileage on my 06 after I loaded the power commander with a smoothness map. Mileage between 32-37 2 up loaded not really taking it easy but not drag racing either. Mpg calc reads 2-4mpg higher. Thinking of going to stock supplied map and see how that goes. On the 06 at least though it really helps the throttle since below 3k rpm it's very notchy stock.

Forgot to mention tbs done, new spark plugs and clean air filter. Large vstream shield/dash shelf and topbox on always. Average over past 2 weekends/1500 miles. I think alot of people exaggerate their mileage and average at sea level shifting at 4-5k running 5-10 over is 38-43mpg. Not sure if some people get a 142hp bike and then run on the highway at 10 under to get great mileage but sometimes I suspect.

 
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BTW. I'm thinking of exporting a f150 lariat limited 6.2ltr, has anybody got the new model and what is their opinion, good and bad?

Andy
I have an 05 Lariat and want to upgrade. Ford came through town recently to host a drive and learn at the local race track. They had the V6 turbo, the 5.0, and the 6.2. I drove both the V6 turbo and 6.2. That 6.2 was amazing. Really torquey. The 0 to 60 was like 6.5 to 7 seconds consistently in 4WD high (slightly snowy day). Motor is amazing. But two other things I loved was the dash. LCD with full menu system at the center of the dash between speedo and tach shows everything you could imagine about the truck. The other thing I loved was the brakes. I just updated to aftermarket pads and slotted rotors which made my truck much better then stock, but the 2011's brakes are unbelievable. I also liked how you can disable gears. This is a great feature when pulling a big trailer up a huge hill. You can disable the top 3 gears and just use the bottom 3 to keep the RPMs in the power band. The guide also demoed the active steering which was amazing with a cross wind. Overall, its a huge upgrade over my truck. I'd buy one in a second if I didn't just buy a new FJR.

 
I only wanted the tuning of the PC3 for the near WOT stuff, and from what information I have gathered on here and elsewhere, the O2 sensor is not going to play a role in those situations. Cruising and other partial throttle applications my bike runs great stock.

If I am wrong about the system operating in open loop during 60-100% throttle, someone please tell me.
Well....damn. I never considered that possibility. I guess that makes sense. It doesn't make a lot of sense to install a PC3 just for that limited role, but I guess it would work for what you intend it for.

Nobody really knows for sure, but conventional wisdom and some general language in the SM say that yes, the FI is operating in open loop mode during hard throttle. I still think there is a possibility you are trying to 'out-engineer' the two systems by doing this, but what the heck.

 
SKoot - you're right. Basically I don't need the PC3. My bike never surged, never ran lean, never ran hot stock. It runs great without the PC3 even with my full header Muzzy system. It may decel pop until I have one bar on the temp gauge, then it doesn't. Nonetheless Muzzy basically gave me the PC3 for nearly free, so I installed it with the full system. Any of the 'canned' maps makes my bike run rich, feels like it's a little bogged down, and I would get the typical piss poor mileage - which really bugs me, nothing pisses me off more than the thought of a fricken 1.6L Civic next to me on the highway getting better mileage than my 622lb wet FJR.

So I set the whole left side (pretty much 20% throttle and below) to zero, which leaves the stock FI completely untouched, and figured I'd get a little more up top from the aftermarket maps I have tried. The bike rips so hard my butt dyno can't even tell a subjective difference. Either way I get well over 40mpg on the highway and about 36-38 running the bike really hard in the 100mph plus range when I play on back roads with R1s, etc.

I may just sell it.

 
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