96 F150 with check engine light on
06-02-2007, 06:44 AM
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96 F150 with check engine light on
I have an in line 6, 4.9. I have replaced both o2 sensors, egr valve and the solonoid for the egr over the past 2 years. Now I have a catalyst code, o2 code and heater code. Shot the cat with a heat gun and got 50 degree increase inlet vs exit. I was told 40 to 50 degrees is what is expected from a functioning cat. I hate to keep throwing parts at it, but I have to get this right. Are there any quirks with this year and model that drive this? It runs fine. The more I talk to folks the more I get the feeling that this is not an exact science with any viehicle. Am I at the mercy of trial and error?
Last edited by campfire2u; 06-02-2007 at 06:51 AM. Reason: more data
06-05-2007, 08:30 PM
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P0420 Catalyst efficiency below threshold (bank 1) Thats what came up on Smitty's hand held unit. Sound familiar? Contrary to what I posted before this is the only code showing now. Bank 1, is this in reference to the upper o2 sensor?
Last edited by campfire2u; 06-05-2007 at 08:33 PM.
06-06-2007, 07:02 AM
#4
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Catalyst below threshold means that cat is bad. Sounds like the downstream o2 is working. Need to replace the cat(s). Bank 1 is Refrencing the sensor before the cat. If its a straight 6 its the sensor for Cyls 1 2 3.