Contour Enthusiasts Group Archives Forums General Troubleshooting OBD-II Error code

A friend of mine used his OBD-II scanner on my Contour after the check engine light came on. Got the following code: P0301. Scanner said it was a cylinder #1 misfire. Also when checking the O2 sensors B2S1 wasn't changing. It stayed at 99.02 for a reading.

Here's some info on my car. 2000 Contour SE ATX Duratec V6. 42,000 miles. The check engine light has blinked 4 times before, but only when the car was in 3rd gear and the tach reading above 4000 RPM (like when passing someone). When it blinked I let off the gas, the car shifted to 3rd, and a few seconds later the blinking stopped. When it blinked their was no code left for OBD-II.

Any help/advice is greatly appreciated. Like where I could find, on my car, the O2 sensor that isn't changing what it reads.

Dunno what to say about the O2, check to make sure it's plugged in properly?

For the OBD-II code:

From Ford Service Manual:

First thing it says to check, assuming you haven't recently run out of fuel (which your symptoms don't suggest) is to check the crank pulley for wobble. If the pulley wobbles while the engine is running, replace it and reset the PCM (disconnect battery for 5 minutes).

If not, move on to this:

Next is a check fo the DPFE sensor. DPFEEGR value reading should be within 0.15 volts when comparing key on engine off and engine on values. The value MAY be accessible using your friend's OBD-II tool. If you are using the Alex Peper tool, it would probably be under the "Enhanced" menu.

Next is a check of the coil pack, which is something a dealer or mechanic familiar with Ford PCM controlled spark systems should do by the test methods description I read.

If that checks out OK, move on to the fuel injector harness and injector (#1 in your case). Check harness resistance between PCM pin 71 and 75 (#1); should be between 11 - 18 ohms.
If that checks out, the injector should be flow tested. Basically if everything else checks out, it is more than likely a clogged/faulty injector.

I'll try those. Thank you for you detailed response.

I would include here a careful visual inspecion of the #1 spark plug and #1 spark plug wire. While you are at it, swap the plug with any other cylinder if nothing else shows up.

Look for any build up on the plug. Consult a plug condition chart if necessary. Make sure the plug is gapped properly. On the plug wire, especially look for pin hole leaks in the area of the spark plug well. Sometimes they show up as a little white dot where it has blown through. The reason for swapping the plug is to see if the problem moves to the other cylinder as witnessed by the code next time the code is set.

If it gets down to the point that an injector is suspected, swap the injector with another cylinder to see if the problem follows the injector. Most certainly run a can of Techron or Red Line injector cleaner through the tank if there is any doubt.

I remember a case like this receintly that turned out to be a dirty connection at the injector. It was VERY hard to find. Final solution was very easy.

Also sometimes a revised engine calibration will have slightly looser misfire parameters. It is possible that there is really nothing wrong and the code is being set because the specs are too tight. It might be worth checking to see if the is a revised calibration that can be made. This must be done by the dealer. He must use the WDS, SBDS, or NGS to reflash the prom in the PCM.

Let us know what you find so that we all can learn.

By the way, the response from PA 3L SVT is excellent.

I printed this page up, and bringing it to my friend that works on my car. I'll let you know what happens. Thanks again for the help.