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reflash made my fuel economy go to hell

Old 05-03-2004, 09:54 PM
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reflash made my fuel economy go to hell

I just had a re-flash a few weeks ago because the tranny started shifting in and out and in and out of o.d. etc.,

The re-flash they did caused my "in town" mileage to go from 390 miles per tank (till the light came on) to about 310 miles per tank.

I was afraid that might happen (reading some of the forums, etc., lead me to believe that this might be the norm)/.

The shifting points went up quite a bit. So now, if I am on the freeway going 35. It never even sees the last two gears.

I am getting quite the runaround from dodge.
The best story is "our hands are tied when it comes to the software" because of smog rules and such.

How can burning an extra 6 or 7 gallons of fuel for every 390 miles be reducing emissions?????

Does anyone know the solution to this problem. DOdge is not part of the solution..is my guess. Is there a chip or something I can buy to change the shifting points back to where they were????

I do not tow. But I believe if you do a lot of freeway towing at 35 to 40 miles per hour,.. without ever seeing the last gear or overdrive.....ARENT YOU JUST ASKING FOR A BURNED UP TRANNY/??
Somewhere I read that the tranny really needs to be locked up into overdrive in order to create the least amount of heat and the most amount of efficiency.
ANway, if anyone has any ideas on this, will they please let me konw.
Thanx,
Old 05-03-2004, 11:57 PM
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i think your main problem is "cruising" the freeway at 35. what's that all about? i don't get good mileage at that speed in any gear. but i hope you get it worked out. good luck
Old 05-04-2004, 12:18 AM
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You must not have lived in Los Angeles.
Crusing at 35 is Involuntary, I assure you. I'd rather cruise at 65.
And sometimes do if I'm lucky.

The main point is, my driving habits DID NOT CHANGE when the re-flash was done. Only the fuel economy changed. The fuel economy did not "go" down, so to speak. It changed from one point to another the instant the reflash was done. So we know for sure it is not anything else . (for that matter, the VP44 and lift pump were both changed last fall. and I've been adding Lucas upper cylinder lubricant ever since (that statement came out from bosch concerning california diesel fuels being too low in sulphur for their liking.) I would add the stanydine they had tested, but cannot find anyone in my area that carries it.
Old 05-04-2004, 01:08 AM
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oh, man. i was out there for some training last year and was heading back from santa monica to city of industry about 7:00 PM. it was like the world stopped. i can't see how you can take it day after day. i'm sure you're exceeding the recommended max idle time. . i don't need them flashing my EEprom if that's the case. can't tell what your driving, but you might what to ask the rest of the group what they think about using the hypertech or superchips tuner, they write to the chip and might give you some of that lost mileage back. later
Old 05-04-2004, 08:56 AM
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Your flash for trans shift issues updated the JTEC controller (jeep/truck engine controller which only oversees the drivetrain on the CTD equipped trucks), NOT the ECM (cummins controller) which overseas all the engine functions. The only "shift points" that could have been altered electronically are the OD and lock up clutch engagement mph. 1-2/2-3 can be adjusted with the throttle psi cable to some extent. Anything I tow at 45 mph would be too low of an rpm to use OD and would abuse the lockup clutch. Add your truck and options to your signature so we know whatcha got!
Old 05-04-2004, 09:24 PM
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My truck is 98 1/2 24 valve quad cab 3/4 ton with a tow package.
Auto tranny. 2wd.

No mods.

I'm not sure what you are saying. Are you saying that the re-flash could not have done it.

This is very hard for me to believe.

My shifting points were definitely at lower speeds beforehand. And throughout the time I've had the truck. It used to be in OD much sooner.

Now, because I see the HUGE difference in mpg. I figured this may be some mistake. Not on purpose....surely. I'm sure the epa (and all other similar muckymucks) wouldn't be delighted to hear that dodge is helping me burn lots more fuel.

Since I don't tow. I can't see the point of lower gears when I'm not accellerating.
Old 05-05-2004, 09:11 AM
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I am kinda curious about this subject, I had the reflash done as well and my average went from 19.2 to 17.4. Same driving style and routine.
Old 05-07-2004, 09:59 AM
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I am almost positive it is because they changed the shifting points. Mine were definitely at a higher RPM aftger the re-flash,.

Still am looking for box or something that will let me change the shifting back to lower rpms. I do not tow anything.
Old 05-07-2004, 09:05 PM
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All this talk about "reflash", Is this the same procedure done by the Hypertech device? Or am I missing something...
Old 05-08-2004, 12:04 AM
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Reflash is a slang term for "software re-installation, or software upgrade. Or, in some cases, like mine.... "downgrade".

Basically, the computer begins to forget itself (which I do not believe for one minute, after all my research, I believe there is probably electronic "noise" that is not shieded out completely..And at some point it begins to interfere...Even though, for some reason, a re-flash will eliminate this problem for a while. I believe it will probably eliminate the problem "for a longer time" if the new software doesn't try to shift until at higher points. So I would bet that is the ONLY reason the re-flash is at a higher point than the original. It is fine to shift at higher points if you are accellerating, or pulling. But there is absolutely no reason to run down the road at 40 mph and have NO CHANCE IN HELL of being lockeed up into overdrive and even having to be lucky to have it in high.


It appears there are "some" who have "eliminated" this problem completely with either filtering or shielding, but I don't even know what to shield or filter. Or I would do that immiediately. I own a recording studio and have usually done all my own electronic troubleshooting......and getting rid of electrical noise and interference is not hard to do.

And at some point dodge had expressed some interest in some type of shielding or filtering that someone had done and eliminated the problem without having software re-installed.

I don't know anything other than that. Which is why I'm hoping someone will reply to this and let me and everybody else know....Is there a box or something I can buy?
Old 05-12-2004, 07:47 PM
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Re-Flash

My 98.5 idels at 800 RPM. It is hard to feel the shift points, unless you really step on it. But mine in O.D, will be going about 40-45 MPH, when it kicks in. Your truck is regestered in Cal, That might effect your re-flash problem, state laws, Etc. Mine was done in Il, and it is way different than yours, even though we drive the same year truck, and equiped the same. If you would know someone from Nevada, with the same truck, It would be interesting to compare them. I just fueled the truck 4 hours ago, and paid $ 1,70.9 for diesel.And went 409 miles on 22 gal of fuel. The last few days I have been putting about 100 miles on the truck each day. When I pull my camper, I will get about 12-14 MPG, It is in the # 10,000 Lb class.
Old 05-18-2004, 05:15 PM
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Re: reflash made my fuel economy go to hell

[QUOTE]Originally posted by Puke
[B]I just had a re-flash a few weeks ago because the tranny started shifting in and out and in and out of o.d. etc.,

The re-flash they did caused my "in town" mileage to go from 390 miles per tank (till the light came on) to about 310 miles per tank.

I was afraid that might happen (reading some of the forums, etc., lead me to believe that this might be the norm)/.

The shifting points went up quite a bit. So now, if I am on the freeway going 35. It never even sees the last two gears.

I am getting quite the runaround from dodge.
The best story is "our hands are tied when it comes to the software" because of smog rules and such.

How can burning an extra 6 or 7 gallons of fuel for every 390 miles be reducing emissions?????


Dodge auto shifts at 1-2 at 1600-1800 rpm under 20mph, 2-3 at 1600-1800 rpm under 30 mph and into od under 50 mph, lock up occurs about 5 secs. later. Under light accelleration.
You can adjust the throttle valve cable to lower the 1-2 and 2-3 shift points. Just change it by an 1/16" at a time till the shift points suit you.
I
Old 05-19-2004, 11:17 PM
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Adjusting the throttle valve cable sounds like an easy fix.
However, I haven't looked too close under there yet....a cummins mechanic told me that there is no longer a direct linkage from your footpedal (throttle) to the motor,...he said it is actually controlled by a computer and you just think your foot is directly controlling it. This made me afraid to go much further.

SO, having said that... WHERE IS THE THROTTLE VALVE CABLE AND WHAT DOES IT LOOK LIKE. Is there any chance I will adjust the wrong thing??:

Ok,
Thanx for the replies.
Old 05-20-2004, 08:29 AM
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It's a cable that runs from the TPS down to the transmission. You unclip it and slid it foward or back to adjust the throttle pressure. Better get a service manual if your not sure.
Old 05-20-2004, 09:28 PM
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Service manual, huh.

Which one??? At some point a few years back (about 95 or so) I guit buying factory service manuals. I guess that was about the time they all started wanting mechanics to pay for an online service or something. I just noticed that the last two I bought were garbage (as far as true factory manuals go) and quit buying them.

So do I need to get a "Dodge " one? Or a "Cummin's" one (is there such a thing??? ) Or is there some other manual? I would love to have one if it is worth buying....But I am guessing the Haynes type manuals are barely worth the paper they are written on....Their definition of "complete, including A/C" is for them to tell you to take it to an A/C place. Ha ha. The first time I read that in a manual I almost thought it was a joke.

Anyway, let me know on which manual is a good one. And I am guessing the last thing they are ever going to give us is an electronic schematic to the CPU for the motor OR the truck. But at least I can wish. (I'm sure either a capacitor or resistor or inductor would let me change the shift points also). I think they've been in court over that one for a few years (with independent mechanic's).

Ok,
Thanx for the post

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