RX7Club.com


Go Back   RX7Club.com > Generation Specific > 3rd Generation Specific (1993-2002)
Sign in using an external account
Register Forgot Password?
Register Photos FAQ Members Search Today's Posts Mark Forums Read Used CarsVendors TSB & Recalls Garage
Welcome to RX7Club.com

Reply
 
 
 
 
LinkBack Thread Tools Search this Thread Display Modes
Old 07-13-05, 02:16 PM   #1
Spinner
 
Trader Score: (0)

Join Date: Jan 2003
Location: Tucson
Posts: 100
gettomg 5mpg need help

What can cause the car to be getting this kind of fuel effinecy? I've just about given up hope on fixing this car. street ported motor and PFS purple computer with supporting mods.
youngin is offline   Reply With Quote
Old 07-13-05, 02:55 PM   #2
Cheap Bastard
10 Year Member
 
adam c's Avatar
 
Trader Score: (2)

Join Date: Sep 2002
Location: San Luis Obispo, Ca
Posts: 7,427
If you are driving the car really hard, and always around town, 5 mpg is possible. I suggest that you do a highway-only run, and check it again. You should be able to get close to 20 mpg while cruising on the freeway. I get 9 mpg around town, mostly easy driving, and 23 on the freeway.
adam c is offline   Reply With Quote
Old 07-13-05, 03:01 PM   #3
Living on Borrowed Time
 
Nghtstlkr7's Avatar
 
Trader Score: (0)

Join Date: Nov 2003
Location: Prowling the streets of NoVA
Posts: 444
Send a message via AIM to Nghtstlkr7
^i get about the same with full exhaust and port. maybe a bit better than 9mpg around town though. ive managed 26mpg twice during my cross country trip.

have you thought about checking your O2 sensor. a bad one could cause you to get terrible fuel mileage.
Nghtstlkr7 is offline   Reply With Quote
Old 07-13-05, 03:02 PM   #4
King of the Duct Tape
10 Year Member
 
airborne's Avatar
 
Trader Score: (0)

Join Date: Feb 2001
Location: PA
Posts: 1,176
i average 15mpg w/street port and splitting time between 10 and 15lbs of boost. fuel leak?
airborne is offline   Reply With Quote
Old 07-13-05, 04:36 PM   #5
Spinner
 
Trader Score: (0)

Join Date: Jan 2003
Location: Tucson
Posts: 100
I was getting an error that it was not recieving a signal from the O2 sensor so I replaced it but Im thinking now that the wire was cut somewhere. I do not boost the car at all and its easy driving throught town. I basically pour out black smoke on occasion and my plugs are black and sometimes wet when I check them with fuel. The problem is not from driving habits.
youngin is offline   Reply With Quote
Old 07-13-05, 04:40 PM   #6
Spinner
 
Trader Score: (0)

Join Date: Jan 2003
Location: Tucson
Posts: 100
The injector were cleaned while i was rebuilding the engine and i checked the connections and what not today and they are all correct. If they were seated in bad would this cause them to stick open at times? It runs rough at low rpms but if you accelerate right around were you would start to boost it seems to stat to clear up and run fine with no misfires.
youngin is offline   Reply With Quote
Old 07-13-05, 05:49 PM   #7
No Life.
 
kuroi FD's Avatar
 
Trader Score: (0)

Join Date: Jan 2005
Location: orlando/st. petersburg
Posts: 769
if an injector was sticking open it wouldnt start easily and or flood and you would definetly smell the gas out of the exhaust
kuroi FD is offline   Reply With Quote
Old 07-13-05, 06:02 PM   #8
Spinner
 
Trader Score: (0)

Join Date: Jan 2003
Location: Tucson
Posts: 100
Well I had some issues with flooding right after I put it back togather but it starts fine every single time now. So I dont know whats going on with that. Would the O2 sensor really cause it to run this shitty if it was bad. It basically runs like **** untill you get to a point when you are about to boost or when you boost and then it seems to clear up. This would lead me to believe it is something to do with the O2 sensor but Im not for sure. Is it set to read off the O2 sensor untill boost and then read off the map sensor and run on premapped fuel maps instead?
youngin is offline   Reply With Quote
Old 07-13-05, 06:49 PM   #9
FD title holder since 94
 
Tim Benton's Avatar
 
Trader Score: (0)

Join Date: Mar 2001
Location: Cedartown, Ga
Posts: 4,049
Send a message via AIM to Tim Benton
Since you don't have a wideband, do you have the data acq software for the computer? What is the 02 voltage when your driving under different circumstances? If it's pegged at .8 and higher all the time, then your running super super rich.

Tim
Tim Benton is offline   Reply With Quote
Old 07-13-05, 08:06 PM   #10
Spinner
 
Trader Score: (0)

Join Date: Jan 2003
Location: Tucson
Posts: 100
Dont have any software for it, but Im getting an error code from the O2 sensor even after I replaced it with a new one.
youngin is offline   Reply With Quote
Old 07-13-05, 08:08 PM   #11
Spinner
 
Trader Score: (0)

Join Date: Jan 2003
Location: Tucson
Posts: 100
I know Im running extremly rich because of the fuel smell the carbon build up on my plugs, the carbon build up on my bumper after a couple days of driving, and the excesive black smoke and flames out the exhaust.
youngin is offline   Reply With Quote
Old 07-13-05, 08:21 PM   #12
Spinner
 
Trader Score: (0)

Join Date: Jan 2003
Location: Tucson
Posts: 100
just checked it and its code #17 which is the Feedback system for O2 sensor. How do I go about fixing this problem if it might be whats causing my fuel problems. Another simple questions which color tops are the primiarys and the secondary injectors.
youngin is offline   Reply With Quote
Old 07-13-05, 10:27 PM   #13
Spinner
 
Trader Score: (0)

Join Date: Jan 2003
Location: Tucson
Posts: 100
Well just to let everyone know I think I finally figured out my problem. Either me or my friend switched the injectors around. Everyone thought it was not possible but it happened. I am about to start the pain staking process of switching them back. Wish me luck lol
youngin is offline   Reply With Quote
Old 07-13-05, 10:27 PM
RX7Club
Mazda RX7




Paid Advertisement


 
 
 
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


All times are GMT -5. The time now is 12:36 AM.
All content Copyright © 2007 by Internet Brands, Inc.

Contacts

SEO by vBSEO ©2010, Crawlability, Inc.