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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Afterfires under load

  • Thread starter Thread starter Fox8950
  • Start date Start date Sep 2, 2007
F

Fox8950

Member
Jun 29, 2007
247
2
18
Sep 2, 2007
#1
  • Sep 2, 2007
  • #1
Hello all, finally getting enough miles on my new motor to start putting my foot in it a little more and I ran into a tuning issue. Any time you smash the pedal its slow to bring up the rpm and causes a few intermittent afterfires out the exhaust as it does. If you give it about half throttle (which WAS the most it had for a bit due to breakin) everything acts fine and it accelerates great, feels like it has plenty of power. I've pretty much done what I could to troubleshoot it and think it may be ignition related (have 8mm taylor wires with about 4 years on them and original factory coil that are suspect atm). Was hoping for a little bit of feedback before I started throwing parts at it
 

dcurtis

10 Year Member
Jan 19, 2006
688
7
39
Sep 3, 2007
#2
  • Sep 3, 2007
  • #2
Are you getting enough air/fuel?
 
F

Fox8950

Member
Jun 29, 2007
247
2
18
Sep 3, 2007
#3
  • Sep 3, 2007
  • #3
Well I assume theres plenty of fuel if its dumpin enough out to ignite in the exhaust and air filter is brand new, other than that I dont have a way to tell right atm. I did check the rail pressure though and was all fine.
 

jrichker

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Sep 3, 2007
#4
  • Sep 3, 2007
  • #4
Dump the codes and see what the computer says is wrong…Codes may be present in the computer even if the Check Engine light isn’t on.

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.

See http://www.troublecodes.net/Ford/





IF your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.



89 through 95 cars have a working Check Engine light. Watch it instead of using a test lamp.



Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.

Or for a nicer scanner see http://www.midwayautosupply.com/pc-7208-90-equus-digital-ford-code-reader-3145.aspx – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $30.
 
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