strange fuel cut (limp-home mode?) - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


General Miata Chat A place to talk about anything Miata

Reply
 
 
 
LinkBack Thread Tools
Old 02-09-2008, 06:35 PM   #1
Elite Member
Thread Starter
iTrader: (24)
 
kotomile's Avatar
 
Join Date: Oct 2006
Location: Monterey, CA
Posts: 7,578
Total Cats: 40
Default strange fuel cut (limp-home mode?)

Best way I can explain it is to say the car flat refused to go over 2400-2500 RPM immediately after a short WOT burst in 2nd gear. I pulled over and popped the hood for my checks. No leaking pipes (still have AFM), no unplugged sensors, etc. Everything checked out. With the engine still idling I reached for the throttle and turned it slightly by hand, engine speed increases but only to 2400ish, then hits a wall, and [---] is indicated on the UEGO gauge.

The really strange part is that after I'd decided to get off the interstate (!) and limp it home through some back roads, it went back to its normal, rev past 2400 RPM self. I put my foot in it some and it felt fine, boost and all.

WTF happened?????
kotomile is offline   Reply With Quote
Old 02-09-2008, 08:00 PM   #2
I'm Miserable!
iTrader: (5)
 
bryantaylor's Avatar
 
Join Date: Dec 2006
Location: jacksonville, fl
Posts: 1,720
Total Cats: 0
Default

loose ground?
bryantaylor is offline   Reply With Quote
Old 02-09-2008, 09:21 PM   #3
:(
iTrader: (7)
 
Join Date: Jul 2006
Location: nowhere
Posts: 8,281
Total Cats: 2
Default

hmm i am thinking ignitor trouble. Maybe by the time you decided to pull off the interstate the ignitor had cooled and gone back to working properly.
magnamx-5 is offline   Reply With Quote
Old 02-10-2008, 11:51 PM   #4
Elite Member
Thread Starter
iTrader: (24)
 
kotomile's Avatar
 
Join Date: Oct 2006
Location: Monterey, CA
Posts: 7,578
Total Cats: 40
Default

Maybe, I don't think it would be a loose ground, although the engine was out twice a month ago I tightened the grounds down well, plus I don't think that sort of thing would get better on its own, you know? Like it would only get looser with time?

Magna - what about it points to ignitor problems? Curious. If it is the ignitor that's a perfect excuse to go CoP! Should I be interpreting the [---] displayed on the WB gauge as a fuel cut?
kotomile is offline   Reply With Quote
Old 02-10-2008, 11:58 PM   #5
I'm Miserable!
iTrader: (5)
 
bryantaylor's Avatar
 
Join Date: Dec 2006
Location: jacksonville, fl
Posts: 1,720
Total Cats: 0
Default

Quote:
Originally Posted by kotomile View Post
Should I be interpreting the [---] displayed on the WB gauge as a fuel cut?
yup
bryantaylor is offline   Reply With Quote
Old 02-11-2008, 12:01 AM   #6
Junior Member
iTrader: (12)
 
Join Date: Oct 2007
Location: Central, NJ
Posts: 487
Total Cats: 1
Default

Are you running a megasquirt on HiRes code by any chance?
MikeRiv87 is offline   Reply With Quote
Old 02-11-2008, 12:13 AM   #7
Elite Member
Thread Starter
iTrader: (24)
 
kotomile's Avatar
 
Join Date: Oct 2006
Location: Monterey, CA
Posts: 7,578
Total Cats: 40
Default

Nope, still on the "stock" greddy FPR and stock injectors, which perplexes me.
kotomile is offline   Reply With Quote
Old 02-11-2008, 12:16 AM   #8
Junior Member
iTrader: (12)
 
Join Date: Oct 2007
Location: Central, NJ
Posts: 487
Total Cats: 1
Default

ok that rules out that. A few of us with MS and HiRes where having a very similar 2500rpm fuel cut.
MikeRiv87 is offline   Reply With Quote
Old 02-11-2008, 01:51 AM   #9
Elite Member
Thread Starter
iTrader: (24)
 
kotomile's Avatar
 
Join Date: Oct 2006
Location: Monterey, CA
Posts: 7,578
Total Cats: 40
Default

Good looking out anyway, then!
kotomile is offline   Reply With Quote
Old 05-27-2011, 01:12 AM   #10
Newb
 
Join Date: May 2011
Posts: 1
Total Cats: 0
Default

Quote:
Originally Posted by kotomile View Post
Good looking out anyway, then!
mines having the same problem, i just drove it for the first time today and it starts cutting out between 2000 rpm and 2500 rpm's. any help?
rbecher7 is offline   Reply With Quote
Old 05-27-2011, 01:35 AM   #11
Elite Member
iTrader: (4)
 
MartinezA92's Avatar
 
Join Date: Aug 2009
Location: Mountain View, CA
Posts: 1,702
Total Cats: 28
Default

Quote:
Originally Posted by rbecher7 View Post
mines having the same problem, i just drove it for the first time today and it starts cutting out between 2000 rpm and 2500 rpm's. any help?
Old thread is old. Also, you're doing it wrong.
Go intro yourself or something.
MartinezA92 is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Project Gemini - Turbo Civic on the Cheap Full_Tilt_Boogie Build Threads 57 07-19-2017 05:11 PM
Need help - Stock Balancer and Fastforward overlay pulleys Frank_and_Beans Supercharger Discussion 13 09-12-2016 09:17 PM
Walbro 255lph Fuel Pump $50 lsc224 Miata parts for sale/trade 2 10-01-2015 10:17 AM
"Chimney Ethanol" E100 MiataGarage Engine Performance 5 09-30-2015 12:04 AM
Got bad Crank Angle Sensor and Random Misfire codes, but runs fine. Greasyman General Miata Chat 2 09-28-2015 11:44 AM


Thread Tools

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 Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 02:56 PM.