Engine Hesitation on 2000 Ford Windstar

I'm still having problems with my van. We put new fuel injectors in and it ran great. Now, the check engine light is back on. We got thr codes read at Autozone. They indicated lean on banks 1 and 2 and misfire on #2 cylinder. The guy at Autozone said it was most likely a MAF sensor. My question, could this also be causing the misfire? If not what in the hell is doing this? Please help solve this mystery.

by in Vincennes, IN on October 06, 2010
2 answers
ANSWER by , October 06, 2010
First, let's look at the P0302 - for the cylinder #2 misfire. This is likely unrelated to the P0171/P0174 codes. You may have a plug or wire issue at the #2 cylinder, or perhaps have an issue with the fuel injector or wiring you replaced. (what reason caused you to replace the injectors? these are usually not an issue...) The P0171 and P0174 bank 1 and 2 lean codes could be a MAF sensor, and could be related to a vacuum leak, such as an intake manifold gasket leaking. HOWEVER...it is MUCH more likely that the cause is something else. There is a Technical Service Bulliten that addresses these codes specifically. It suggests there is a loose fitting vacuum line (your vacuum leak) at intake manifold where the line goes to the fuel pressure regulator. Oil is swelling the line and causes it to become loose. The direction is to replace the left side valve cover (with a newly designed valve cover to prevent oil from getting where it does not belong), and to replace the upper to lower intake manifold isolator bolts and gaskets. Somewhat more elaborate than a simple repair, but definitely effective. I have overseen dozens of these common repairs. This most assuredly should solve your issue. The first thing to do is check the vacuum line to the fuel pressure regulator at the intake manifold to see if it is indeed loose and swollen from contamination. Good luck!
ANSWER by , December 21, 2010
I HAVE A JUNK THAT IT'S LIKE YOURS TOO. while you spent time to fix it, you rather use that money to buy a seanna. I had this goody for five years and only change oil.