Well guys today I bought an oxygen sensor since I got a code 42 and it's the factory Sensor. Well I've been posting about this but i'll start from the beginning one more time. A while back it started surging badly and killing me on gas so I first cleaned the IAC. Then i changed the TPS and still no luck. The truck surges badly and black smoke roars from the exhaust not to mention 4mpg in city and 6 on the highway. Well I bought the code scanner and got a code 42 on a KOER test and then i tested the voltage going to the oxygen sensor and it was fine. I replaced it today and didnt help a bit, I'm not sure if it matters or if it's even an issue but the only other thing I've found that could be out of place is the haynes manual and the Ford service cd says 10.5 volts to the IAC and im getting 12.2 everytime with key on. But that and the code 42 is the only erros I have found. Any suggestions as where to go with this now?

 

The 10.5 reference is the minimum acceptable voltage. It should be the same (+/- .1v) as the voltage at the battery.

Did the code 42 return after you replaced the O2 sensor? If it did, remove the PCV valve and run the KOER test again, and see if the code returns.

Post your results.

 

If I'm not mistake (and I am at times) a code 42 is oxygen sensor too rich wich I would believe is acurate by the black smoke out the tail pipe. You should'nt runn it too much pig rich because it can burn up the Cat. and in some cases mess up O2 sensors along with foul plugs. Without readoing your old posts, have you pulled the vacuum line off the fuel pressure regulator. Should not have any fuel there. Do you have data stream on you code reader, MAP and Coolant temp readings could be nice, maybe even IAT. Post your results with the PCV valve out KOER test results.

 

Hey thanks for the replys. I just finished rerunning the test with the pcv valve out. And it did still come with the code 42r even with the new Oxygen sensor in. I checked the fuel pressure regulator for signs of gas and even went as far as placing a Qtip in it and it's not having any signs of fuel. I'm totally lost now as where to go from here. Any ideals?????????


Thanks Guys.


Daniel

 

Which engine do you have?

Next step is to check the fuel pressure with the engine running. If you have a 4.9L, it should be between 45 and 60 psi. If you have any other engine, it should be between 30 and 45 psi.

If your fuel pressure is within specs, turn off the engine, and watch the fuel pressure gauge for 60 seconds. What does it do?

 

I have a 302. I'm gonna try and get the fuel pressure checked tomorrow cause i dont have the tools to check it. Thanks for all the help and i'll post what i find..



Daniel

 

That's cool. Don't forget to watch the gauge for 60 seconds after you shut off the engine! I need to know what the gauge does during that time.

 

Can someone suggest some place maybe online where i can buy a fuel pressure tester? I went to all the parts stores in the town i live (we only have 3) and none of them stock em and say they can order one but dont know when it will be here. I'm needing one bad and does anyone know the average price i should expect to pay for it?

Thanks.....


Daniel

 

Sears sells a decent one.

 

thanks i made the order tonight..........



Daniel