P1131,P1151,P0174, P0304, P0306 2000 Ford Expedition

I have several failure codes on my 2000 Ford Expedition.(as stated in the subject line) It has 145K miles. It is running rough especially around an RPM of 1500.

Originally I only had a P0304 code (cyclinder 4 misfire). I changed the plug and cop. (much fun!) It seemed to run better during the test drive but has sense deteriated. I didn't clear the codes after changing the #4 plug and cop. The plug that I changed was white-ish pink (lean?) I also changed the PCV valve and associated elbow.

The instrument gave me a message of Manufacturer Control Fuel Air Metering for the P1131 and P1151 error codes.

Any other ideas?

thanks, bea

intake gasket vaccum leak? dirty MAF?

Thanks Jeff.
I checked the MAF sensor inside the air intake. It looks clean. As far as checking the intake gasket; how would you suggest I go about doing that. It looks hard to get to so I may thinking of the wrong thing.
thanks, bea

I cleaned the MAF sensor with CRC MAF cleaner. It seems to run a little better but is still pretty rough. I also checked for vacuum leaks but couldn't find any.

Do I need to reset the PCM or just allow time for retraining?

thanks,
bea

I now only have the original P0304 code. I replaced the COP and plug and checked to see if I was getting significant spark. It was.

The Expy is still running very rough at 1-2k RPM. Can anyone tell me how to check the injector or any other ideas?

thanks, bea

To check the injector you can pull off the entire fuel rail and leave the injectors connected and have someone crank the engine while you watch them spray. It should look like a fine hairspray mist.

First off though, especially if it has the plastic intake, I would check for intake leaks and vacuum leaks. You can do both at once with a can of WD40.

Thanks! How do you use the WD-40 to check for leaks. I've never done this?
bea

a haynes or chilton manual will tell you how! if ou don't have obne get one or google it!