KOEO Codes = My car is hardly drivable - MustangForums.com

5.0L (1979-1995) Mustang Technical discussions on 5.0 Liter Mustangs within. This does not include the 5.0 from the 2011 Mustang GT. That information is in the 2005-1011 section.

Thread Tools Search this Thread
Old 07-13-2010, 06:31 PM   #1
3rd Gear Member
Thread Starter
Join Date: Dec 2007
Posts: 717
Default KOEO Codes, car sputters, CEL flashes and causes rough driving. Help please!

Hello everyone. My car is currently embarrassing to drive. It sputters, and drives/decelerates extremely jerky.

I ran a KOEO with the actual machine decoder i borrowed from a friend, here are the random codes i got.

96 - Fuel Pump CKT

91 - Left EGO Lean

63 - TPS Low

41 - EGO Switch

31 - EVP/EPT Circuit

A few comments - This is the first time i have had a fuel issue. Both my O2's are brand new, in a BBK O/R H pipe. I have no idea what/where the EGO switch is. I have fixed my TPS before and i had it set up properly before the car started to run like crap. The Left bank being lean is a normal occurrence and i have yet to fix it. ( usually the right bank is reported lean too. ) Im pretty sure the EVP/EPT Circuit is the vacuum line 'containers' behind the passenger strut tower, but i have no clue whats wrong witt the circuit. There's no visible damage back there ( if im even looking at the right things )

Its a 1990 5.0L with a stock engine. Headers, BBK o/r H pipe, and a few suspension upgrades. Smog pump is still hooked up along with all the vacuum lines. The H pipe did have a hole for the smog pipe.

Any input is greatly appreciated!

Last edited by Bobert; 07-13-2010 at 10:19 PM.
Bobert is offline   Reply With Quote
Old 07-13-2010, 06:31 PM   #2
3rd Gear Member
Thread Starter
Join Date: Dec 2007
Posts: 717

Oh also, the car has stalled out on me alot too. Which never happened before. This would be while the car is attempting to idle at a red light. ( Idle is extremely rough )
Bobert is offline   Reply With Quote

Related Topics
Thread Thread Starter Forum Replies Last Post
2008 Airbag error code 51 Elcameeeno 2005-2014 Mustangs 1 08-19-2015 12:19 PM
Groaning noise coming from rear when turning right 92 5.0stang 5.0L (1979-1995) Mustang 4 08-13-2015 07:46 AM
FORD FRENZY!!! Milan Dragway-September 12th Milan Dragway Members Rides and Car Show Section 0 08-12-2015 04:43 PM
Need Help Diagnosing Have Codes (Confused) djbigskrilla 2005-2014 Mustangs 13 08-11-2015 01:59 PM
Trans issues codes P0732 P0735 P0775 Mnuckolls 4.0L V6 Technical Discussions 3 08-09-2015 09:54 AM

1990, 1995, 50, 50liter, 90, 96, car, code, codes, fix, ford, gt, koeo, mustang, randomly, reading, sputtering

Thread Tools Search this Thread
Search this Thread:

Advanced Search

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

Forum Jump

Featured Sponsors
Vendor Directory

All times are GMT -5. The time now is 03:38 PM.

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.