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Dan M
Dodge Dakota
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7/17/2007
13:43:07
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 Subject: ign advance
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Message:
i'm looking for some input on this.
I have an 02 QC 4x4 and my friend has an 03 QC 4x4. both with 4.7L autos.
according to my scanner I run at ~11 deg advance and his dak runs at ~4 deg advance.
He gets ~12 mpg and i get ~16 mpg.
both are electronic ignition.
any ideas why he gets so bad gas milage compared to me and why the ign advance is so differnet?
neither 4.7 are h/o. His has 50k and mine has 80k miles. I checked his O2 sensors with my hand held scanner (factory - maybe denso as mine were??) and they are switching good, not running rich for any extended period of time.
he's always gotten around 12-13 mpg.
another difference i noticed my map sensor is around 10.5 while his is around 12.
- Dan M
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1hotkadota
Dodge Dakota
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7/17/2007
14:47:29
| RE: ign advance
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Message:
Do you both have the same tranny?
How well does he maintain his engine, maybe he needs a tune up.
Or he has a lead foot.
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Dan M
Dodge Dakota
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7/17/2007
17:44:09
| RE: ign advance
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Message:
A tune-up was recently done on his in an effort to improve his milage. As I said, he's always gotten this kind of milage. he maintains it as well as I maintain mine - we both follow a regular schedule of fluid changes, etc.
- Dan M
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Kowalski
GenIII
7/17/2007
18:01:28
| RE: ign advance
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Message:
Not all 4.7's have the same amount of advance. Many years ago, when I was looking into a custom flash for mine, someone posted they had seen at least 4 different amounts of advance for stock 4.7's; there may be even more. The 4.7 responds quite well to ignition advance. While there may be other differences, your extra advance could be at least partially responsible for the milage difference - making better power could be returning better milage.
Lead, follow, or get out of the way
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1hotkadota
Dodge Dakota
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7/17/2007
18:19:49
| RE: ign advance
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Message:
Kowalski is right about that.
Do you think he got the death flash like me?
I have an '02 RC 4.7L 4spd auto and when I got the death flash, I noticed it immediately. I took my truck in because I was having trouble with my drivers side window back in 2003 and when I left that day it seemed different. A few months later I was researching these forums and I learned about the death flash. I knew I had it because I went to look at my PCM and there was a sticker there that said "Factory Performance Upgrade" aka DEATH FLASH. I'm guessing they just retard timing to help put less wear on the engine or something.
Tell your friend to check his PCM. The sticker just might be there.
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Kowalski
GenIII
7/17/2007
18:43:22
| RE: ign advance
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Message:
While that sticker might indicate the "death flash", it isn't always that way. I believe a tech once posted it was only those flashes with a suffix after AH (like AI, AJ, etc) that were the death flash. That was posted years ago, info could be out of date - but not all flashes are the "death flash". Timiing light would confirm it though, as has already been noticed. More ignition advance will equal more power, but go too far and you'll need premium fuel. Never actually measured the advance on mine, but it's right where I only needed premium for heavy towing. I don't think I need it any more now I'm running 4.10 gears, but I still use it towing to be safe. Your freind might want to try Superchip - came out after I got my flash. The guys here seem to like it much better than the Jet.
Lead, follow, or get out of the way
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Dan M
Dodge Dakota
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7/18/2007
06:39:13
| RE: ign advance
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Message:
Thanks guys, i forgot all about the death flash. I'll have him check the version. From doing a quick search, it looks as though the version ended in AB that was the "death flash".
- Dan M
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1hotkadota
Dodge Dakota
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7/18/2007
11:57:28
| RE: ign advance
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Message:
Thanks for the research Dan M and Kowalski. I wasn't sure which suffix it was.
Now i have to go check my PCM and see which "upgrade" the stealership gave me.
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jasonsdakota
Dodge Dakota
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7/30/2007
17:40:25
| RE: ign advance
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Message:
is there a superchips for 2004 4.7 with auto for my dakota?
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jasonsdakota
Dodge Dakota
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7/30/2007
19:31:30
| RE: ign advance
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Message:
ok, no there isn't.
new question.
is there any tune or custom flash for the 2004 4.7 dakota automatic?
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duh uh?
Dodge Dakota
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7/30/2007
22:19:00
| RE: ign advance
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Message:
Where is the PCM?
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Dan M
Dodge Dakota
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7/30/2007
22:26:55
| RE: ign advance
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Message:
What does pulse code modulation have to do with automobiles?
- Dan M
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daddio
Dodge Dakota
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7/31/2007
09:46:03
| RE: ign advance
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Message:
PCM = power control module. located on the passenger side fender.
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