Intermittant CEL getting a code 41 | Ford Explorer Forums - Serious Explorations

  • Register Today It's free!

Intermittant CEL getting a code 41

cybergasm

Explorer Addict
Joined
January 8, 2006
Messages
6,421
Reaction score
19
City, State
Humboldt Ks
Year, Model & Trim Level
1997 Mountaineer 5.0
For last few weeks i have been driving my 1991 X with it transplanted motor from a 1993 ranger back fitted to my 91 everything has been fine but in the last week it has started popping a intermittant CEL on the dash.

Like i said the motor running fine except for maybe a little surging at part throttle especailly when it cold.

So today i ran my code scanner on it and both KOEO and KOER test both came back with code 41 my scanner reads "exhaust gas oxygen switching not present- always indicating lean"

now is this the O2 sensor that is being refered too? this motor did have an EGR on it but my 1991 did not so i trashed it and everthing related to it
and reused my 1991 intake manifold and exhaust header with the EGR port plugged.

can anybody confirm this before i run out and buy an new O2 sensor?
which is what i believe the problem is.
 






KOER and CM 41 both mean that the computer is seeing an incorrect signal from the O2 sensor. Whether it is from a faulty O2 sensor or not is still up for debate. Sometimes the engine is really running lean and the O2 sensor is simply reporting the truth.

It is possible to get a "false" KOER 41 if you don't preheat the sensor immediately before the test. Where you have a CM 41 (I'm assuming this isn't some old, leftover code), I doubt that is an issue, but it's worth mentioning.

Where you've recently had the engine out, probably the first thing I would do would be to check the wires going to the O2 sensor. Many have accidently got those wires pinched in between the transmission and the engine or laid them across the exhaust.
 






mine turn out to be a combention of fuel pressure regulater solved the ideal problem and running rich and purge valve that made it act like choke stuck when first started
 






Back
Top