My Experience with Eco Tune from GDE

Ripster · **Posted:** Mon Sep 21, 2009 5:09 pm

Wife and I drove down to Ohio last week and Keith from GDE met up with us as we passed by Fenton Michigan.

All of the mods you can see in my sig. Across the UP I was able to get 29 mpg and about 27 on the freeway at
70. We left Fenton and the freeway for the next 50 miles or so is very flat. I reset the EVIC and saw 40 in the first
few miles, then it settled down to 37.9 and I could not break that barrier. Stopped for fuel, it dropped in the 36 range.
Back on the freeway and it worked itself back up 37.9 I am now in Ohio and after Mansfield through the town, out
to two lane roads, out to dinner, I am still show an average of 35. This vehicle has never made it past 29 and stayed there.

Another benefit is I have boost and egt gauges, with the MAG unplugged I dropped 100 degrees, I plugged the
maf back in. Across the UP and freeway I was getting just over 700 in egt. NOW I am at 500 to a shade
under 600 at 70 on the freeway with the AIR on. This is really amazing to me and should really help cool the
engine, --heck by the time by I stop I am at 400 --where I generally shut down.

On the return trip ran 75mph and was always around the 36mpg mark, with 550 EGT temps.
I did a hand calculation, I expected a 2-3 mile drop from the EVIC. I have stock size tires, and in my example
240 miles and 7 gallon is 34mpg, while the evic, showed 36.8 and .7 of a gallon makes a swing of 4 mpg. So
while the EVIC shows large numbers, the real story will be less. And this vehicle does not lend itself to burping
and having the fuel in the neck like the VW would do with the vent removed and full on at all times.

So if I fill up more one time and then it kicks off sooner for whatever reason the swing could go the other way.
So the EVIC is off, don't know if the tune could address that in software to come closer, or with the variables
of tires, it would be a lost effort. So the average from Grayling Mi freeway and across the UP two lane was
approximately 34mpg. I will, when I have more time, put the fuel in the neck for several tanks and see
what a true hand calculation would be.

It is a great tune and very smooth. Now when a check engine light is there, it will be for a reason. Had the
lights changed in the brain while I was at it, now the extra lights are on for both high and low beam.

CATCRD · **Posted:** Mon Sep 21, 2009 6:00 pm

I have seen the same thing with the GDE tune. The EVIC is 5 mpg optimistic, but the mileage is still better than stock.

stoutdog · **Posted:** Mon Sep 21, 2009 7:39 pm

Two things:

1) Are you saying you got a hand calculated of 34mpg going 75mph? That's quite impressive, if so, as my GDE tune yields 36mpg at 60mph and more like 32mpg at 70.

2) The EVIC, for me, varies wildly with this tune. The last time I filled up, after a trip @65mph in a huge sandstorm/monsoon, downhill, the EVIC read 48.6mpg! I had an actual of 33

Ripster · **Posted:** Mon Sep 21, 2009 8:03 pm

No the 34 was overall with 3 hours at 75 and 4 hours at 65, sorry about that. The EVIC
is fun to watch, however I would say 5 is about right, still about 4-5 mpg better than
stock and the heat reduction through the turbo is impressive. Cools down fast.

Trekker · **Joined:** Tue Jul 21, 2009 11:42 am **Posts:** 33

Just in from my first road trip on my new 05 CRD. Installed the GDE eco tune last week.

My trip was 600 miles, from SE Utah to central AZ, with lots of elevation change as I passed through Flagstaff.

Total mileage for the 600 miles: 29 mpg overall.

I had hoped to do better, but my oversized off-road tires may be hurting me. (New thought: I have no idea if my odometer is correct with these tires. Guess I need to get out the GPS...)

nursecosmo · **Posted:** Tue Sep 22, 2009 1:34 am

Ripster wrote:

Another benefit is I have boost and egt gauges, with the MAG unplugged I dropped 100 degrees, I plugged the
maf back in. Across the UP and freeway I was getting just over 700 in egt. NOW I am at 500 to a shade
under 600 at 70 on the freeway with the AIR on. This is really amazing to me and should really help cool the
engine, --heck by the time by I stop I am at 400 --where I generally shut down.

Are you saying that the EGTs improved when unpluging the MAF WITH the GDE tune?

Joe Romas · **Posted:** Tue Sep 22, 2009 6:31 am

Trekker wrote:

Total mileage for the 600 miles: 29 mpg overall.

I had hoped to do better, but my oversized off-road tires may be hurting me. (New thought: I have no idea if my odometer is correct with these tires. Guess I need to get out the GPS...)

My results are similiar and I'm very happy with them :lol:

What is really outstanding is my 25 MPG short trip city driving :shock:

My odometer with oem goodyears is around 4% low :wink:

Winter fuel is just around the cornor so get all the good MPG's while you can :cry:

Ripster · **Posted:** Tue Sep 22, 2009 6:32 am

No I have not unplugged the MAF with the tune. I got a 100 degree drop with just the maf unplugged.
Then once plugging it in after the tune, the temps went down another 200 degrees from where they
were with the maf unplugged before the tune.

Original temps maf connected stock 800
maf unplugged no tune 700
maf plugged in with tune 500 level ground 70 mph

nursecosmo · **Posted:** Tue Sep 22, 2009 9:46 am

Ripster wrote:

No I have not unplugged the MAF with the tune. I got a 100 degree drop with just the maf unplugged.
Then once plugging it in after the tune, the temps went down another 200 degrees from where they
were with the maf unplugged before the tune.

Original temps maf connected stock 800
maf unplugged no tune 700
maf plugged in with tune 500 level ground 70 mph

Gotcha.

ac5501 · **Posted:** Tue Sep 22, 2009 10:53 am

Ripster wrote:

No the 34 was overall with 3 hours at 75 and 4 hours at 65, sorry about that. The EVIC
is fun to watch, however I would say 5 is about right, still about 4-5 mpg better than
stock and the heat reduction through the turbo is impressive. Cools down fast.

Somebody else reported heat reduction in the turbo after the GDE as well. That was the deciding factor for me to go with this tune.

I just got done doing a very similar trip. From Port Huron to St Ignace (semi truck show) this weekend. Coming up Sat. morning it was really cold, and we had to use the heat a lot. Which, as you may know turns on the AC compressor :evil:

. That combined with 75 mph avg speed and a day and a half of city driving gave me a 30.1 for that tank of fuel. For the return trip, it was 70mph with no AC. I have not yet refiled the tank, but it looks like it will come in around 34-35mpg.

linewarbr · **Posted:** Tue Sep 22, 2009 12:57 pm

ac5501 wrote:

Ripster wrote:

No the 34 was overall with 3 hours at 75 and 4 hours at 65, sorry about that. The EVIC
is fun to watch, however I would say 5 is about right, still about 4-5 mpg better than
stock and the heat reduction through the turbo is impressive. Cools down fast.

Somebody else reported heat reduction in the turbo after the GDE as well. That was the deciding factor for me to go with this tune.

I just got done doing a very similar trip. From Port Huron to St Ignace (semi truck show) this weekend. Coming up Sat. morning it was really cold, and we had to use the heat a lot. Which, as you may know turns on the AC compressor :evil:

. That combined with 75 mph avg speed and a day and a half of city driving gave me a 30.1 for that tank of fuel. For the return trip, it was 70mph with no AC. I have not yet refiled the tank, but it looks like it will come in around 34-35mpg.

Using the heater shouldn't turn on the A/C Compressor?

ac5501 · **Posted:** Tue Sep 22, 2009 1:13 pm

linewarbr wrote:

ac5501 wrote:

Ripster wrote:

No the 34 was overall with 3 hours at 75 and 4 hours at 65, sorry about that. The EVIC
is fun to watch, however I would say 5 is about right, still about 4-5 mpg better than
stock and the heat reduction through the turbo is impressive. Cools down fast.

Somebody else reported heat reduction in the turbo after the GDE as well. That was the deciding factor for me to go with this tune.

I just got done doing a very similar trip. From Port Huron to St Ignace (semi truck show) this weekend. Coming up Sat. morning it was really cold, and we had to use the heat a lot. Which, as you may know turns on the AC compressor :evil:

. That combined with 75 mph avg speed and a day and a half of city driving gave me a 30.1 for that tank of fuel. For the return trip, it was 70mph with no AC. I have not yet refiled the tank, but it looks like it will come in around 34-35mpg.

Using the heater shouldn't turn on the A/C Compressor?

No it shouldn't. But unlike any other vehicle on the planet, It sure does on the Liberty. There are instructions on how to disable this "feature" with pictures on this site. I think I'm gonna do that before winter sets in. Lets call it my next mod.

chrispitude · **Posted:** Tue Sep 22, 2009 4:30 pm

Many vehicles turn on the A/C when running the defroster (even in heating mode). I've never seen one that runs it with vent heat.

Do you have a link to the modification instructions?

- Chris

ac5501 · **Posted:** Tue Sep 22, 2009 5:13 pm

chrispitude wrote:

Many vehicles turn on the A/C when running the defroster (even in heating mode). I've never seen one that runs it with vent heat.

Do you have a link to the modification instructions?

- Chris

Actually..... you have seen one.....every day.....its most likely parked in your driveway even as we speak :lol:

Well technicaly our Jeeps don't turn on the AC Comp if your using just the upper vent setting. Defrost, Defrost/floor, floor, vent/floor all turn on the AC compressor.

I have been looking for the thread that details the mod, but no luck so far. I did post the question on this forum so maybe we can get a response soon.

RTStabler51 · **Posted:** Wed Sep 23, 2009 4:46 am

I wish I wasn't stuck in DC traffic to see the fuel economy numbers you guys are seeing! I'm lucky to get 21mpg, but that's about 2mpg better than previously. I tell myself its for the driveability! However, I do get about 19mpg now towing, up from about 16/17mpg previously.

dgeist · **Posted:** Wed Sep 23, 2009 10:08 am

ac5501 wrote:

chrispitude wrote:

Many vehicles turn on the A/C when running the defroster (even in heating mode). I've never seen one that runs it with vent heat.

Do you have a link to the modification instructions?

- Chris

Actually..... you have seen one.....every day.....its most likely parked in your driveway even as we speak :lol:

Well technicaly our Jeeps don't turn on the AC Comp if your using just the upper vent setting. Defrost, Defrost/floor, floor, vent/floor all turn on the AC compressor.

I have been looking for the thread that details the mod, but no luck so far. I did post the question on this forum so maybe we can get a response soon.

Well, the windshield needs dry air to defog, so check on that one. Your feet, to avoid foot fungus and frostbite, also need dry air, so check on that one as well. It all makes sense

linewarbr · **Posted:** Wed Sep 23, 2009 11:56 am

ac5501 wrote:

chrispitude wrote:

Many vehicles turn on the A/C when running the defroster (even in heating mode). I've never seen one that runs it with vent heat.

Do you have a link to the modification instructions?

- Chris

Actually..... you have seen one.....every day.....its most likely parked in your driveway even as we speak :lol:

Well technicaly our Jeeps don't turn on the AC Comp if your using just the upper vent setting. Defrost, Defrost/floor, floor, vent/floor all turn on the AC compressor.

I have been looking for the thread that details the mod, but no luck so far. I did post the question on this forum so maybe we can get a response soon.

Now wait a minute. Mine has a button with a little snowflake on it that I have to push to get A/C. If I leave it on vent/ floor, the compressor doesn't come on - or at least if it does, it is not noticeable. Because when I punch the snowflake, the fact that the compressor is on is very noticeable. Louder diesel clatter with a distinct sense of the engine working to turn the compressor wheel. I have never noticed it with it set on vent/floor unless I press the A/C button itself. However, I only run the heater for maybe a total of 75 days down here, so I've never paid attention to it when I have the dial cranked over to red.

A/C does come on automatically when I spin over to one of the defrost settings.

Joe Romas · **Posted:** Wed Sep 23, 2009 12:35 pm

linewarbr wrote:

If I leave it on vent/ floor, the compressor doesn't come on - or at least if it does, it is not noticeable.

Better check again closely :shock:

Having it on in the floor position will also help dry out the carpet. A dry carpet won't rust the floor eather :lol:

grywlfbg · **Posted:** Wed Sep 23, 2009 9:27 pm

I don't think "bi-level" turns on the A/C. Just the two defrost settings and floor. But yeah, if you dig around in this forum there's a way to disable that. I believe it involves cutting a contact off of the selector knob so when it's in the floor mode it won't also touch the A/C contact. But find the real instructions :wink:

Ripster · **Posted:** Thu Sep 24, 2009 6:34 am

Can we get back to GDE and start a new thread reference AC on with what settings.

My Experience with Eco Tune from GDE

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