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what to do to make rx-8 more fuel efficient ?

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Old 10-17-2011 | 08:19 PM
  #26  
TYork's Avatar
2004 RX8 Engine #2
 
Joined: Apr 2011
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From: Austin
Check to make sure that the fuel pump outlet is not cracked and leaking gasoline (it was on my 2004). Also check for vacuum leaks; the three black plastic 1/4" fittings on the intake bellows is a good place to start.
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Old 10-17-2011 | 09:25 PM
  #27  
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Originally Posted by 8 Maniac
That was a really intelligent post. It's not like he's complaining about 17-18 mpg. 7 mpg is absolutely not normal and I'd imagine a lot of us would never have bought an RX-8 if that was typical mileage.
Yeah, sorry OP and club members. I saw the thread title and instead of reading through his post I just assumed it was another "why my RX-8 no get good mpgs" type of thing and quick replied. Newbie mistake. 7 miles per gallon is a problem, even for an '8.
Old 10-17-2011 | 11:14 PM
  #28  
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First Time Rotory Owner
 
Joined: Oct 2011
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From: WI IL border
Originally Posted by 05rex30
I would also try seafoam
Not sure if this is a dumb question but does that help these out alot and is it safe to seafoam the rotory?
I just got an RX-8 and it feels like it should pull alot harder... feels like it wants to go faster but it like its hold its self back. i plan to check the plugs maybe give it a tune up tomorrow and see how she performs then
Old 10-18-2011 | 09:54 AM
  #29  
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Joined: Mar 2011
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From: Denver, CO
Originally Posted by Red_lineRX-8
Not sure if this is a dumb question but does that help these out alot and is it safe to seafoam the rotory?
I just got an RX-8 and it feels like it should pull alot harder... feels like it wants to go faster but it like its hold its self back. i plan to check the plugs maybe give it a tune up tomorrow and see how she performs then
Everyone has a slightly different opinion on what degree "Seafoam" or any other detergent actually provides in cleaning benefits. Some say little to none, others say quite a bit.

Anyway, sounds like you recently bought your car.
Chances are you should go through all the threads aimed at new owners of used cars, and go through the list of items to help bring your car up to spec in regards to knowing that you have a properly working car.

BC.
Old 10-18-2011 | 10:33 AM
  #30  
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From: Norwood, NJ
OP, didn't read the whole thread yet, but it looks like your there's something wrong with your car. I don't know how you drive it but 3 kpl is very low, even for this car.

Also check your brakes to see that they haven't seized up.

Don't forget to check for gold bullions hidden in the trunk, and always fill up with SUPER UNIQUE.
Old 10-18-2011 | 10:06 PM
  #31  
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Red...lots of people here have an opinion bout it and I had some hesitation and used it and the hesitation went away..I also got a little better mpg for that fill up I usually get a consistent 18.7 but ended up with 19.5
Old 10-18-2011 | 10:11 PM
  #32  
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From: Y-cat-o NZ
Funny - the OP left the building days ago yet everyone is still trying show him the way ....
Old 10-22-2011 | 12:56 PM
  #33  
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thanks everyone ... nothing is perfect when you are buying a recondition car , we need to make it perfect as we want ... thanks to all who suggests me ... I will definitely try to make my car perfect again .
Old 01-11-2018 | 10:51 PM
  #34  
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LA MAZDA RX-8 2004 super poor GAS MILEAGE

I paid $4,000 for my friends 2004 MAZDA RX-8 and have put an additional $1,500 into it including alot of VACUUM and ECG sensores...I am getting approximately 10 mpg with the
6 speed manual...the dealer wants $990 for a tuneup, and 3 solenoid parts ...air filter new...does anyone online have SUGGESTIONS
Old 01-12-2018 | 07:54 AM
  #35  
NotAPreppie's Avatar
What am I doing here?
 
Joined: Mar 2006
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From: 2017 Miata RF Launch Edition
Coils/plugs/wires $310 + shipping (bottom of page)

Air Filter $23.50 + shipping

Solenoids $22.80 each + shpiping
(assuming they are referring to the 3 vacuum solenoids on the back of the UIM. I've used these on my '8 and they work perfectly.)

Total: ~$400 + shipping.

All of these are relatively easy items to do that don't require anything more special than a basic mechanic's toolkit from Horrible Freight.

Total with tools: $531.90 + shipping

While you're at it, you should get a
$15 Elm327 Bluetooth OBD-II adapter $15 Elm327 Bluetooth OBD-II adapter
and a $10 phone app so you can pull data from the car like fuel trims, MAF rate, AFR, coolant temp. All this stuff makes troubleshooting easier.

Last edited by NotAPreppie; 01-12-2018 at 07:57 AM.
Old 01-12-2018 | 09:15 AM
  #36  
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Originally Posted by filmdoctor
I paid $4,000 for my friends 2004 MAZDA RX-8 and have put an additional $1,500 into it including alot of VACUUM and ECG sensores...I am getting approximately 10 mpg with the
6 speed manual...the dealer wants $990 for a tuneup, and 3 solenoid parts ...air filter new...does anyone online have SUGGESTIONS
What you need are probably coils and spark plugs. They're easy to change yourself and available at NAPA or similar. . Its extremely rare to need to replace all 3 solenoids unless there is a check engine light for a specific one.
Old 01-13-2018 | 11:14 AM
  #37  
delhi's Avatar
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Joined: Jul 2003
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From: Home of the NIMBYs
Originally Posted by filmdoctor
I paid $4,000 for my friends 2004 MAZDA RX-8 and have put an additional $1,500 into it including alot of VACUUM and ECG sensores...I am getting approximately 10 mpg with the
6 speed manual...the dealer wants $990 for a tuneup, and 3 solenoid parts ...air filter new...does anyone online have SUGGESTIONS
For starters you bought an 04. Secondly there's no good rx8 at that low price. The ones I see here under $5k are all having engine issues. Anyway atleast it runs. Money saved put into the above suggestions and hope that's that.

About​​About mileage rotaries are terrible in stop and go traffic. Also winter gas formula hurt mileage too. I see about 10-15% drop during winter time. But that could be a combination of more accessories running and lumpy winter tires.
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