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o2 sensor question

  • Thread starter Thread starter zzstang
  • Start date Start date Jan 1, 2008
Z

zzstang

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Nov 8, 2006
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Jan 1, 2008
#1
  • Jan 1, 2008
  • #1
I have a 90 gt and it smells like it is running very rich. When I first start it up it runs great, after a few minutes the idle goes way up then drops way down to the point where it will stalls sometimes. I did just notice that the 02 sensor is broken and I dont know if that would cause the problem??? The motor is a 306 with gt40 upper and lower, 24 #er's, c/l76 meter,frpp t/b and a novi 1000. I just installed all of the parts. I did have the same problem before the build. Any help would be great.Thanks
 

jrichker

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Jan 1, 2008
#2
  • Jan 1, 2008
  • #2
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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