So, I got codes read on my CEL, and got P0171 (lean bank 1) and P1406 (EGR-specific, think it'* pintle stuck open?). So, I cleaned my MAF, cleaned my EGR and replaced the gasket, and my CEL is, as of today, cycled but still on. I'm not sure what to do next. The EGR was actually in decent shape, so it seems unlikely that it'* to blame. With that in mind, what else would cause a P1406 if not the EGR valve? I'm thinking possibly a vacuum leak, but I don't know, and I wouldn't know how to check for one either. Any thoughts? There are no real drivability issues except perhaps a bogging/loss of power at highway speeds (above 60 mph).

Disconnect the battery for 30 minuets, that will reset the code. See if it comes back.

DTC P1406 Exhaust Gas Recirculation (EGR) Position Sensor Performance

When I start the car after having disconnected the battery, the CEL comes right back up, no delay. This makes me think it'* something electrical, a faulty connection or maybe a dead part. Thoughts?

When you cycle the key can you hear the EGR valve move? If not, replace the solenoid.

Check for the following conditions:

• Open EGR ignition filter circuit. An open in the EGR ignition filter circuit will cause erratic EGR Position Error readings while the EGR valve is operating. With the ignition ON, a test light should illuminate when connected between ground and the EGR ignition filter circuit at the PCM connector. If not, locate and repair the open in the EGR ignition filter circuit.
• pink wire pin 68 PCM connector C1(blue)
• Excessive deposits on EGR valve pintle or seat. Remove the EGR valve and check for deposits that may interfere with the EGR valve pintle extending completely or cause the pintle to stick.
• Poor connection or damaged harness. Inspect the wiring harness for damage. If the harness appears to be OK, observe the Actual EGR position display on the scan tool while moving connectors and wiring harnesses related to the EGR valve. A change in the display will indicate the location of the malfunction.
• EGR Valve Icing. EGR valve icing can occur during cold ambient conditions. An EGR valve icing condition will affect EGR system operation by causing the pintle to stick in the closed position. If DTC P1406 sets, EGR system operation may be inhibited for the remainder of the trip.

Reviewing the Fail Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set

Hey guys, sorry to necro my thread but I wanted to let you all know I fixed my problem! The MAF sensor was going bad, so I replaced it with a junkyard part for 30 bucks...it'* been a week now, and the CEL is gone (before, the longest it stayed off was about an hour). Additionally, the bit of low-end hesitation that was there when the old MAF was being used (when I cycled the light off, before it came back on) is gone.

For anyone in the Detroit area, I highly recommend Scrapbusters in Wayne, MI. They have a decent selection, and 30-day warranty on parts.