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problems

  • Thread starter Thread starter Graydon5oh
  • Start date Start date Dec 13, 2006

Graydon5oh

Member
Nov 23, 2002
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ARKANSAS
Dec 13, 2006
#1
  • Dec 13, 2006
  • #1
ok here is the deal its a 86 with a low millage motor. smog deleted and doesnt have o2s on it at the time but used to not have this problem not running right has a lil bit of miss, and when i floow it, it starts by lugging then a couple hundred rpms later it gets better but still not like it should be. replaced the ingnition module helped a lil. new wires and plugs, fuel injectors have low millage, i was wondering if tps or map sensors could be a problem. also i have ha tan wire on the harness comming from the white 10 pin connector that is just hanging there i believe it has power from it i unwrapped the whole harnss couldnt find the other end of it. any ideas would help
 
V

v8only

Active Member
Jul 3, 2003
2,378
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49
Dec 13, 2006
#2
  • Dec 13, 2006
  • #2
!!!!!!!

You can't just delete the o2 sensors, the computer relies on those to run right. put the damn o2's back in, and you should see a difference
 

jrichker

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Dublin GA
Dec 14, 2006
#3
  • Dec 14, 2006
  • #3
O2 sensors are not smog equipment that you just rip off and throw away. They are a must have part in order to keep the car in top operating tune. Without properly working O2 sensors, you will have an overly rich mixture, poor performance and idle problems.

The loose tan or orange wire from the fuel injector harness is likely to be the O2 sensor power ground. Attach it to the manifold or to the back of the heads.

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.



See http://www.troublecodes.net/Ford/
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

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.

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/detailedproductdescription.asp?3829 – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $35.
 

Graydon5oh

Member
Nov 23, 2002
215
0
16
ARKANSAS
Dec 14, 2006
#4
  • Dec 14, 2006
  • #4
its wasnt my choice to take them off. there werent on there when i bought the car i have the sensores just havnt got ahold of the the harness, and definitly not having problem with running rich if anything its running lean
 

89streetbeast

New Member
Dec 4, 2006
365
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horton,ks
Dec 14, 2006
#5
  • Dec 14, 2006
  • #5
if you got a fuel pressure guage id test the fuel pressure to see if its within specs. should be around or close to 39psi at idle.
 
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