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Post-REVi Fuel economy report after 2 Tanks

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Old 12-08-2005, 01:34 PM
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dmp
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Post-REVi Fuel economy report after 2 Tanks

First Tank = 16.5mpg
Last Tank = 15.5mpg

Pre-REVi average = 18.5 mpg

Mixed driving, Driving 'normal' most of the day, with one or three WOT-to-redline runs per day, in gears 1 and 2.

Last edited by dmp; 12-08-2005 at 11:12 PM.
Old 12-08-2005, 01:44 PM
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Doesn't really matter as long as you are having fun, right?
Old 12-08-2005, 01:47 PM
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How weird... well, what he said^
Old 12-08-2005, 01:49 PM
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Is it possible you are getting more air into the car and the ecu is dumping more fuel to adjust? When I installed mine I reset the ecu and found the milage was a bit worse after doing that but it works its way back up there.
Old 12-08-2005, 01:52 PM
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i assume you've fixed the idle issue dmp?
Old 12-08-2005, 01:54 PM
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It's probably because you're stomping on the peddle more to test the Revi...
Old 12-08-2005, 02:23 PM
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Originally Posted by ZoomZoomH
i assume you've fixed the idle issue dmp?

Nope...still there. car drops to ~500rpms, studders heavily, and feels like it's about to die...about once every 10? seconds while at idle.



If the damn TB just had an 'idle screw' like every OTHER car i've owned, I'd bump the idle to 1000 and just leave it.
Old 12-08-2005, 02:26 PM
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Originally Posted by Jedi54
It's probably because you're stomping on the peddle more to test the Revi...
I drive it +/- how I did before - I'm hoping things will level out eventually.
Old 12-08-2005, 06:43 PM
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Things will level out eventually. My first tank after the REVi was 13mpg! from 18mpg! After a few weeks I am now getting 18-19. The tone of my box also mellowed a bit from a hollow roaring sound to just a deeper sounding stock engine.
Old 12-08-2005, 06:48 PM
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Thanks Ishu I appreciate the encouragement :D
Old 12-08-2005, 09:27 PM
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I had a problem with mine not idling correctly. Took it in and it turned out the "neutral switch" was bad. Apparently the wiring harness had rubbed through and shorted out the switch which affects the idling when the trans is in neutral (I have the manual trans). They replaced it under warranty which fixed the idling issue. Now I have the issue with what appears to be pinging but I think the plugs need replacing; I have just over 37k miles on the original set. All this made itself apparent after I had installed the CAI; I already had the REVi and RB exhaust.
Old 12-08-2005, 10:06 PM
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Originally Posted by Ole Spiff
I had a problem with mine not idling correctly. Took it in and it turned out the "neutral switch" was bad.
Yeah, that is relatively common problem. Exhaust heat is generally the cause.
Old 12-09-2005, 01:50 AM
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Temp this time of year really kicks the **** out of the mileage. Mine has dropped about 30 miles per tank....I have a record of every tank since new...and the Revi didn't affect the #'s in any significant way...the temp does
Old 12-09-2005, 10:30 AM
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Originally Posted by dannobre
Mine has dropped about 30 miles per tank....
What, at 150 mph? in first gear? Or do you have a 1/2 gallon tank?
Old 12-09-2005, 10:49 AM
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Originally Posted by carbonRX8
What, at 150 mph? in first gear? Or do you have a 1/2 gallon tank?

He's saying he gets 30 fewer miles per tank, not he only gets 30 miles per tank.
Old 12-09-2005, 12:19 PM
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^^That's what I love about internet forums

Common sense is not common!
Old 12-09-2005, 12:34 PM
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who needs common sense when you have psuedo-anonymity

while i haven't changed my intake (or anything), i've noticed that my last 2 tanks have been 1-2 mpg less than usual. so i guess its the weather...or the fuel blend...does the SE get a winter fuel blend?
Old 12-09-2005, 02:11 PM
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I have been told since I can remember that I have no common sence. But I am not common.

Oh, BTW I understand the whole drop in mileage now.
Old 12-10-2005, 07:17 AM
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After I installed my intake, I noticed that my mileage stayed about the same... but my driving had changed. It included a lot more WOT and 9,000 rpm just to hear the sound. It definitely had a positive effect.
Old 12-20-2005, 01:53 PM
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After 4 tank-fulls... a whopping 16mpg - down 3mpg from 'normal'. I'm not on the gas much more than before...still scratching my head as to the cause of the drop-off.
Old 12-20-2005, 01:56 PM
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Try putting back the stock intake for a few tanks and see if your mileage goes back to the earlier level. It will be an interesting test.

I don't know how can you get that much worse gas mileage... mine went a bit up after installing the REVi. Not drastically, just about 1 mpg.

Perhaps this drop has to do with the weather more than anything else?
Still, 3 mpg difference is too much to be just because of that. Hm.
Old 12-20-2005, 02:14 PM
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dmp,

I've noticed a sudden decrease of 20-30 miles per tank, so about 1-2 mpg, since about a month ago. All mileage sensitive factors have remained constant: no changes to the car (bone stock) and driving style, city/highway mix etc. hasn't changed.

I attribute it to the introduction of oxygenated gas for the winter. I expect to see it back up to normal in the Spring.
Old 12-20-2005, 02:20 PM
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I don't wanna go thru the trouble of re-installing the stock intake actually...I'll just live with it, and take my chances on spring bringing better economy.
Old 12-20-2005, 02:29 PM
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Maybe the tire pressure is down due to the cold weather. From what I have read/heard, tires pressure affects fuel consumption by a big margin.
Old 12-20-2005, 02:29 PM
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Originally Posted by Blue87Sport
dmp,

I've noticed a sudden decrease of 20-30 miles per tank, so about 1-2 mpg, since about a month ago. All mileage sensitive factors have remained constant: no changes to the car (bone stock) and driving style, city/highway mix etc. hasn't changed.

I attribute it to the introduction of oxygenated gas for the winter. I expect to see it back up to normal in the Spring.
Oxygenated gas will impact your gas mileage 10 to 20%.


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