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I've been watching the GPH display for about 8 months now.
For several months, I have been backing off the pedal as rpm's increase during a pulse.

Most of my pulses are in 4th gear since I do 95% city driving.
I start the pulse around 25 mph=1900 rpm and about 1.5 GPH.
At first acceleration is sluggish because this thing has pathetic torque.
Once it gets to about 2100 rpm, it starts making more power and GPH hits my 2.0 target.
As rpm's rise to 2600, I back off on the pedal until at the end of the pulse I'm using maybe 1.7 GPH.

The acceleration actually stays pretty constant from 2100 to 2600.
When I was experimenting with a constant TPS throughout, I would end up using around 2.5 GPH at the end of the pulse.
My feeling is that the added acceleration this gave wasn't worth the skyrocketing fuel consumption.

Some recent results;
Yesterday 27 miles, 49.7 mpg, 20 mph avg, 2636 rpm max
The day before 23.8 miles, 45.8 mpg, 20 mph avg, 2844 rpm max.
These are a full day of driving so it's out and back, not just the downhill part.

My suggestions:
You're revving it too high. Try a max of 2200 instead. That may mean a shift to 5th halfway through the pulse.
Watch the LOD gauge instead. Keep it constant in the ~75 range.
Let the GPH climb with your speed. That's ok. Keeping the rpm lower will keep it from consuming too much.

Hi Andrew,
I don't always rev to 2600, sometimes I'll top out closer to 2400. It depends on whether I'm pointed uphill or down
Problem with this car is the torque is pathetic until around 2100 - maybe it's the altitude here, I dunno.
If I don't rev higher, the acceleration is so slow I don't think it would qualify as a 'pulse'. I'd have tailgaters climbing my rear constantly instead of just most of the time.
Maybe what I should do is time some of my accelerations, then we would have something quantifiable for comparison purposes.

Also, this is my work vehicle. my weight is 2980# vs stock curb weight of 2395#. This is about 25% more weight...

Joel, I won't presume to know the best way to drive your particular vehicle but on the topic of slow pulses I do have to point out that my Insight is probably slower yet... and low speed P&G without high RPM does yield very real results. It is how on good days in the summer I can top out over 130mpg in that car where cruising would have me at maybe 90mpg.

Well guys, your feedback and reading the 'SG/shifting for economy' thread has got me thinking.
I will try keeping the peak rpms lower. Because this car has really poor torque in 4th (+5th) that means I will run 3rd gear all the way out to 2200 rpm. What I had been doing with 3rd was shifting early to 4th so I could get the advantage of the more efficient ratio. As Wayne puts it "Soft, short and quick" was how I had been running my first three gears. Now I'll run 1st and 2nd that way and run 3rd gear out a bit further to avoid the sluggish accel in early 4th. Additionally, I'll change my pulse start and finish points to something more like 1900 to 2250 instead of the old numbers (1800 to 2600).
We'll see how my results work out.
Thanks!

Because this car has really poor torque in 4th (+5th)

My car is 107 hp compared to your 108, and 2300 lb compared to your 2395. Very similar power/weight proportions. I think you can easily run lower rpm, down to 1500 or so. Try and see.

Edit: I just saw your note above about the added weight. Yeah, 1500 ain't gonna cut it.

I'm on a road trip in my SE-R, so I can't check GPH on my xB's pulses. I did find pulsing from 25-40 mph in 4th gear at 83 LOD works well as my bread and butter pulse in my xB. That's about 1500-2200 rpm.

My suggestions:
You're revving it too high. Try a max of 2200 instead. That may mean a shift to 5th halfway through the pulse.
Watch the LOD gauge instead. Keep it constant in the ~75 range.
Let the GPH climb with your speed. That's ok. Keeping the rpm lower will keep it from consuming too much.

Just a question about this,
I thought P&G pretty much meant a push in a single gear from speed x to y, then coast down to x and repeat. How many are using gearshifts as part of their pulse?

Thanks! -Joel

Hi, Joel -- I do shifts if I absolutely have to but avoid that for sustained P&G cycles as much as possible. I agree with Andrew on the max RPM... though I'll let it go to 2300 (close enough).

It depends on the terrain. Most of my pulses are timed to uphill segments, so I can glide over the top and down the back side. If it's worth extending the pulse another 5 mph to get there, I might shift. Or sometimes I do a Pulse-shift-dwl-glide thing instead.

I need advice on P&G until as I save up for a Scan Gauge. I have a 2002 Pontiac Montana, 3.4 v6 4 speed auto. It does have an instant MPG gauge and I have been adjusting pulse and glide based on how fast, how frequently and long I can push it to its 99mpg limit.

I typically drive ~20 miles @ 45mph on a city road with timed lights fairly flat the whole way. Some of my pulses and glides are dictated by lights and traffic. Other times I get to choose.

Given my scenario any suggestion on how long to pulse / glide? the fuel cut off seems effective down to around 1200rpm. That's my trigger to pulse. I move the rpm up to between 1800 and 2200 for 5 to 10 seconds, based on traffic. If no traffic, I go until instant mpg falls below 50.

The results are positive so far. I started around 24 and with advice from MadMaxx on Fuel Cut Off its gone up to 25.5 avg indicated. Since trying initial pulse and glide, its gone from 25.5mpg to 27mpg avg indicated, however there was a tune up between those two readings. I probably won't need gas until next week.

Any comments, suggestion and discussion are appreciated

Shift to neutral for the glides, you should glide for longer.

Try to increase your trip MPG with each glide.

Use about 1/3 throttle if you can go that heavy without the transmission upshifting on you. If not, then back off until it doesn't upshift.


....Or ditch the auto, and get a manual transmission. Preferably a CRX! ;)

-soD