Mis-Firing, Need Help - 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 03-14-2007, 09:29 PM   #1
Senior Member
Thread Starter
iTrader: (4)
 
Join Date: Oct 2006
Location: Tampa
Posts: 780
Total Cats: 0
Default Mis-Firing, Need Help

1996 1.8L 90000 miles

The problem with the mis-firing has again reared its head. Between 3500-4000 rpms. Doesnt do it all the time. But, when it does it is in the morning when its cooler and during the day. Let me explain what has been replaced thus far....
New NGK plugs
New NGK wires
Vacuum checks out ok, no leaks
New Walbro 190lph HP pump
New Fuel Filter
Clean Air Filter

So where does that leave me? Coil Paks?????
I am not getting any codes from the ECU.

PS
I am not bitter
96rdstr is offline   Reply With Quote
Old 03-15-2007, 03:18 PM   #2
Junior Member
 
Join Date: Jan 2007
Location: EXTREME Southern Illinois
Posts: 281
Total Cats: 0
Default

I don't think a bad coil pack will only cause a problem in a narrow RPM range. Does it only missfire when you're on boost?
DammitBeavis is offline   Reply With Quote
Old 03-15-2007, 05:27 PM   #3
Senior Member
Thread Starter
iTrader: (4)
 
Join Date: Oct 2006
Location: Tampa
Posts: 780
Total Cats: 0
Default

Nope, I can be running that RPM range, not be in boost and it will do it. I checked the values for resistance and voltage to the MAF and it check out ok. Wits end, I wish I would throw a code so I would know.
96rdstr is offline   Reply With Quote
Old 03-15-2007, 05:34 PM   #4
AFM Crusader
iTrader: (18)
 
olderguy's Avatar
 
Join Date: Oct 2004
Location: Wayne, NJ
Posts: 4,438
Total Cats: 84
Default

olderguy is offline   Reply With Quote
Old 03-15-2007, 05:36 PM   #5
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,847
Total Cats: 1,788
Default

no afm though....
Braineack is offline   Reply With Quote
Old 03-15-2007, 05:38 PM   #6
AFM Crusader
iTrader: (18)
 
olderguy's Avatar
 
Join Date: Oct 2004
Location: Wayne, NJ
Posts: 4,438
Total Cats: 84
Default

Quote:
Originally Posted by Braineack View Post
no afm though....
oops, didn't see the year(or should have looked at the screen name)
olderguy is offline   Reply With Quote
Old 03-15-2007, 06:35 PM   #7
Junior Member
 
Join Date: Jan 2007
Location: EXTREME Southern Illinois
Posts: 281
Total Cats: 0
Default

What's the O2 sensor say right before and right after the missfire? Might help us determine if it's a lean miss, a rich miss, or an ignition miss.
DammitBeavis is offline   Reply With Quote
Old 03-15-2007, 10:20 PM   #8
Senior Member
Thread Starter
iTrader: (4)
 
Join Date: Oct 2006
Location: Tampa
Posts: 780
Total Cats: 0
Default

OK, through luck, I found, hopfully the problem. A wire from the CAS harness was loose. I wiggled it and the car sputtered, wiggled it some more and the car shut off. Fixed the wire, fired it up, went for a drive and no issues...Hopefully, no more issues. Thanks for the help ya'll!!!
96rdstr is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Trying to get started with MS3x BTMiata MEGAsquirt 52 04-14-2014 12:52 PM
Troublingshoot ECU/Car after VVT swap ILoveOffRamps ECUs and Tuning 1 03-15-2014 06:14 PM
MS2 Sync Loss/Fuel Pump Relay Reset Lincoln Logs MEGAsquirt 1 12-11-2013 06:55 PM
Finally, the dyno log railz Dynos and timesheets 7 04-24-2009 01:16 AM
029y3 Problems Aussie Driver MEGAsquirt 0 06-05-2007 07:21 PM


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 07:13 AM.