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My commute primarily consists of rolling hills. This means that I can take advantage of gravity when going downhill and get some excellent coasting but it also means that I have to get back up the other side.

I use the DWL technique but most of these hills require using extra power (and fuel) to get up. What I'm trying to determine is whether I should maintain RPMs as low as possible or downshift and and use higher RPMs to get up and over.

I have a scan gauge so I'm doing some experimenting by watching the fuel burn rate with both of these techniques but I'm open to any and all advice.

Joe

Personally, I have yet to find a situation where downshifting resulted in better fuel economy climbing a hill. I stick to the highest gear that will keep me moving, but generally try to keep the engine spinning between 1500-2000RPM when under that kind of load.

I have CVT so I don't shift, but I do try and keep it in it's highest ratio by keeping engine load as light as possible. If there's nobody behind then I get slower, and slower, and slower and slower.
If the peak is really high with an immediate steep downhill on the other side, I'll creep across the top at only ~20MPH and ride the other side back down, preparing myself for the next hill.
My gauge never going below 40-60MPG all the way up and usually maxing out again for most of the way down.
Just like the little red car in my signiture.

Works for me anyway.

hey liberty don't be afraid to abuse the low rpms in the high gear, we talking about 1100 rpms to hill climb! What you have to learn is to build up speed before the hill. Then when you climb it, make sure your in the highest gear possible (since I find, higher gear you can bleed off your speed much slowly than opposed to low gear) and then as you are beggining to climb. Keep check the LOD feature since it will let you know how hard your engine is working to provide the power you requested (which is usually not much at all since power = gas) I normally try to keep it around 70 when climbing hills and when crusing 30-50 depending on the terrian invovled.

One thing for sure, if my civic with a puny engine that's famous for lugging can climb a hill at 5th, I'm sure your torquey 6spd versa can definiately easily take that challenge on. Just make sure engine load isn't at a ridiculous high level (like 90) and if you do need the power... then okay downshift!

Thanks for the good info. I know what you're saying about going over the top at ~20, Steve.
Fine when no one's behind me.

I've never looked at the LOD feature, Phil. I guess it's probably a better gauge than TPS for DWL.

I followed your suggestion about always using the highest possible gear, Tim. This morning, I believe I achieved my best ever fuel economy for my morning drive - 43.0 - beating my previous best by 0.1 MPG. However, this morning it was ~20 degrees cooler (about 45F).

Hills and mountains produce there own challenges. I have some hills so steep on my test loop that I have to down shift to pull them. Ive choosen to keep these in my test loop as they prove out a facet of real world driving that is incountered here from time to time.

All the advice given so far is text book and the best out there.

If I might add something. FE is our concern here at cleanmpg. At this point I would really work hardist at breaking in the new Verse. I wouldnt lug it around to much nor sore the tach up to redline alot.

Point being as I have broken in the Accord and Civic they have both changed in the way the motor drives and acts as the miles pile on. At over 30k miles the Accord has finely settled down. The Civic at 20k miles is still breaking in.

With the Accord it has settled into liking the bottom end of the tach and lugs around as good as the 5AT will let it. The Civic on the other hand is getting a finer tune on the big end. Truth is the Civic dosent like being lugged around. If it had a taller fith gear it wouldnt like it except for the flatist of roads.

Drive your new car, work on your tatics. But dont be suprized if it throws you a curve. :)

If I might add something. FE is our concern here at cleanmpg. At this point I would really work hardist at breaking in the new Verse. I wouldnt lug it around to much nor sore the tach up to redline alot.


Do you all think I should be varying my RPMs more for the sake of a good break-in? My owner's manual says not to rev above 4K for the first 1200 miles (no problem there) but it is good to drive at varying speeds, which I do on my daily grind but I generally keep the revs in a pretty tight band.

You want to let the engine experience a little bit of everything up to that 4,000RPM limit. That said, psyshack is right and you shouldn't try for maximum fuel economy for a while yet. Vary your driving style and keep the revs moving around. That gets all of the moving parts seated nicely, resulting in the best results over the life of the vehicle.

Do you all think I should be varying my RPMs more for the sake of a good break-in? My owner's manual says not to rev above 4K for the first 1200 miles (no problem there) but it is good to drive at varying speeds, which I do on my daily grind but I generally keep the revs in a pretty tight band.

I didnt mean to subdo your efforts at all. Just get a good soild break in. You will see as time marchs on what Im talking about.

For example: This morning driving the Accord in the torque converter locked at a unheard of 35 mph! Several times I might add. This was wonderful to see. I hope I can replicate it this afternoon for the drive home. It would never do this when it was new. The Accord has the torque to handle this with ease.

With the Civic its getting better higher rpm mpg in certin conditions. For example: With no wind and not to cool or hot temps, it will happly go down, say interstate 40 at 65 mph and turn in a steady 44 to 46 mpg! This keeps the tach under the 3500 rpm max to keep it in its semi Atkins pattern. Meaning,,, basicly its running as a 1.5L engine compared to a 1.8L. But conditions have to be right for it.

You want to let the engine experience a little bit of everything up to that 4,000RPM limit. That said, psyshack is right and you shouldn't try for maximum fuel economy for a while yet. Vary your driving style and keep the revs moving around. That gets all of the moving parts seated nicely, resulting in the best results over the life of the vehicle.

Makes good sense. So, basically, techniques like, DWB, DWL, N-ICE-on coasting, parking smart, etc. are all good but engine revs should vary rather than shifting as early as possible all the time.

Thanks for the great info, guys. I really enjoy this forum and the helpfulness and civility that reigns here.

i have a question about new engine owners. Is it a good idea to FAS it while breaking it in? At what point would abusing FASING be safe for the engine?

How's that LOD feature working out for you farm? I notice it only updates when engine LOD is at a high level (usually 30 and up) and depending on how light you are with the throttle it can vary up and down, once it reaches a certain number for me (like 70) I will downshift or kill the engine if conditions allow :)

hm my gearing is much lower than yours psy and it loves lugging! :D I'm a < 1500 rpms guy that's for sure, and I accelerate from 1000 rpms. Can you believe that I accelerate slower than trucks from a dead stop? yowzers... heck even my patience is tested when I have to trail behind a truck.

I guess I should start FASing behind trucks now instead of lugging the engine ... but honestly what is lugging the engine? Sometimes my LOD doesn't even update when I'm crusing at 50 km/h (30 mph at 5th gear with 1200 rpms) so engine load must mean low! If I were to increase throttle by a far bit that LOD will update and spike towards the 50-80 area depending how much I mash (and 90 if I really step it... never saw a number above that though) but when driving for FE I try to keep it between 0-30 and when climbing hills it starts usually 40 then up... and then pray by the time LOD is at 80 or higher (since lower the speed, lower the rpms, more work for the engine for barely any power.... but barely any gas either ;) the hill will be over and the road will level out. From there on I usually resume the speed I'm at now and increase it slowly since if i know I"ll downshift my LPH (liters per hour) will spike up and I try to keep that number as low as possible.

Good luck Joe ;) I"m jealous of your ride hehe.

Update: Maybe my engine doesn't lug because I'm so light in weight ;) only 130 pounds tee hee. Oh lets not forget my rediculous high tire pressure! (over 60 2 months ago) but I bet its as low as ever since its been harder to physically push my car, as well the weather is getting colder.

Hey, Phil. I've tried FASing in the Versa but it's not part of my repertoire of FE techniques during the engine break-in. I have a few hills on my route where I can coast a long way in neutral. Doing it ICE off would save me 0.2 GPH, according to the SG-II.

I have to confess that after reading about it here, I FASed my Dodge Ram a couple times before trading it in - just to try the technique.:o

I've only been looking at the LOD number for a day or so. The highest I've seen it is low 70s. I think it's about 17-19 at idle (NICE-on coast). 30s cruising on flat.

Yesterday afternoon and this morning, I was more aggressive in my acceleration, taking it up nearly to 4000 rpm a few times and running much higher revs through the gears, cruising at 35 mph in 4th once or twice. I figure I lost about 1.5 MPG on both segments (~4%). Not too much sacrifice for a good engine break-in.

Edit: BTW, Phil, I want to thank you for turning me on to CleanMPG. You posted a link to Wayne's hypermiling article on the NICO Versa forum and that's how I found CleanMPG. If only all the people complaining about the FE of their Versas would come over here!

hey joe I was driving a lot in 5th gear today instead of fasing all over the place, and I had a nice 54 mpg segement (If I know I can hold the FAS for at least 2 mins or so then it'll be worth it or if you predict a green light will go red on you but watch out for those drivers behind you!!) In 5th playing with the throttle at all times allowed me to juggle my instantaneous mpg from 60 to 90 mpg depending on how light I was with the throttle. From there on I was able to maintain 30 mph and I was scoring most of the lights not having to stop (going home from an afternoon shift rocks ;). Most of the time the LOD screen didn't even display so its not even working hard to achive these amazing numbers! The times I press the gas pedal too hard the instantenous goes to 40 mpg and then the LOD starts appearing 30. Now I know ok lugging is bad just try to cruise at lowest LOD possible.

Hm.... I hope that made sense, and hey i'm glad i helped you saved some gas. Those gas companies are sure rich sons of dogs. Hey I forgot to tell you I don't use Throttle sensoring position for the scangauge, I think it updates too slowly (mines a SG I by the way) so I use MAP. What's interesting about MAP is that it syncs with the 4th gear for displaying LitersPer100km. So if the MAP is displaying 8.3 and I'm in 4th gear then that means I consumed 8.3 Litersper100km (try it if your metric ;) what's great about MAP is that I can gauge what is easy, modulate and hard throttle request. Since the MAP is updated much instantly and keeping below a certain MAP (lower the less throttle) allows me to keep me in the optimum fuel economy crusing range. Sometimes when idling and the MAP is constant, it might jump up because of A/C usage or whatever, you can see the increase and guess how much extra throttle your using just to gauge how much FE your accesorries are eating up and cold start operation.

for me 3.3 is the lighest I can go and letting off the gas pedal bring me to the 2 range. between 3 and 6.6 is 50mpg to 100 mpg while 7 to 10 is like less than 50 mpg. In the lower gears, if you have MPG AND MAP displayed, you can really see how much extra gas each gear really contributed to the throttle position.

In other words your feet is the magic! Take her easy Joe!

edit: to summurize my mumbo jumbo, drive in the higest gear possible and use the LEAST AMOUNT OF THROTTLE (the lighter you press the gas pedal) to maintain your DESIRED SPEED. (but at the same time your not losing speed, if you are then just increase it ever so sightly to maintain that perfect point) Your FE Gauges will spikes the highest if you ever get one for your car, of if your car is equipped with it.