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Codes

  • Thread starter Thread starter 86bluecobra
  • Start date Start date Oct 10, 2006
8

86bluecobra

Advanced Member
Dec 20, 2004
4,265
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69
B.C. Canada
Oct 10, 2006
#1
  • Oct 10, 2006
  • #1
This is for a MAPs controlled 302 in a F-150
With the KOER I get these codes 116 which is ECT outside test limits
173 HEGO shows system always Rich
538 Insufficent RPM change during KOER dynamic test
632 Overdrive Cancel switch not changing

I have what feels like a miss in the truck. I guess a studder could also describe it. It used to be in over drive at lower rpm's but now You can feel it in drive while going 1500-2000 rpm aswell. Also not a smooth acceleration from a stop. Kinda a jerky acceleration. When backing the truck up many times it will stall. Black smoke from tail pipes as engine almost dies then surges to higher rpm and back down till it finally dies. Takes a bit of cranking to get it to start again like it is flooded. There was a new o2 sensor installed less then a year ago. I have a comp cams computer controlled cam. .060 over pushrods. Shorty headers off road h-pipe and a flow master cat back. The reverse stall would happen before the cam was installed. Any help would be helpful. I have the TPS set to .82 volts i believe. I cleaned my IAC aswell. My TB was also cleaned thourghly. thx in advance.
 

jrichker

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#2
  • Oct 10, 2006
  • #2
The ECT is the prime suspect in this case. If it reads temperature as being lower than it really is, you will get an overly rich mixture along with many of the symptoms you describe.

Since you didn't include the vehicle year model, the next step may not work correctly. Wiring colors and schemes change year to year and model to model. If the truck uses the same wiring color scheme as the Mustang you have an additional check to make prior to replacing the ECT. Check the resistance between the black/white wire on the ECT & the negative battery post. You should see less than 1.5 ohms.
 
8

86bluecobra

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Dec 20, 2004
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Oct 11, 2006
#3
  • Oct 11, 2006
  • #3
So the ECT is the sensor that tell the computer what the temp of the coolant is? That is a different sensor the the coolant temp that goes to the gauge. If this is the case i Just replaced this sensor because when i removed the intake the last time the old one broke. It is a 92 F-150 with a 302 in it. Do i check the sensor itself or the harness that plugs into the sensor?
 

jrichker

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#4
  • Oct 11, 2006
  • #4
The temp sender for the gauge normally mounts in the driver's side front of the lower intake manifold. It h as 1 wire that connects it to the gauge.

The ECT sensor mounts in the passenger side heater feed tubing. It has a two wire plastic connector.

You want to make sure that the wiring for the ECT is Ok and doesn't have any broken places or bad connections. That's why you measure the resistance of the black/white wire that goes back to the computer's internal ground.



See www.AutoZone.com for wiring diagrams & repair info on your truck
http://www.autozone.com/servlet/UiB..._us/0900823d/80/0a/3a/41/0900823d800a3a41.jsp
 
8

86bluecobra

Advanced Member
Dec 20, 2004
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Oct 11, 2006
#5
  • Oct 11, 2006
  • #5
well I got a code reader and read the codes and preformed the tests it said. The only code i get is 173 system running to rich. With the key on engine running i get a all goode 111 code. When i am driving though it kinda feels like a miss but it isn't a miss. The engine has good power running on all 8 cylinders but when you are cruising at 1500 rpm it kinda bucks a little or stutters a little. Not a smooth ride. Also feels like it does when a rear tire isn't balanced but you feel it in the gas pedal.
 
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