Rough idle?

CRYSTAL DAVIS

MEMBER
2005 LINCOLN LS
3.0L
V6
2WD
AUTOMATIC
59,000 MILES

It's been a hot summer. The car ran great and had cool day car shakes even after engine hot. The next day hot weather again car ran fine now cooler, and cat has a miss at idle it didn't show aby codes for 2 days then got a number 6 misfire and a p2297 "lean at o2 sensor "cleared codes. Has not shown back up but still shakes. Also, I can floor it in park and only revs slowly to about 2,000 RPMS, a TPS or MAF?

thank you

3 Replies

JACOBANDNICKOLAS

MECHANIC
109,755 POSTS

Hi,

The code you have indicates the bank 1 sensor 1 oxygen sensor is out of range during deceleration. When this code is set, the engine is automatically placed in failsafe mode. That is why it won't rev higher than you mentioned. It is designed to prevent further engine damage.

Since there are a few things that can cause this code, we need to check a few things. The first thing is to check for engine vacuum leaks. Here is a link that explains how to check:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

If no leaks are detected, my next question is whether or not there are any exhaust leaks near or before the oxygen sensors. If you don't, then locate sensor 1 on bank 1.

Sensor 1, bank 1 is on the passenger side of the engine compartment near the rear of the engine. See pic below. The pic shows the connector because the sensor is in the exhaust which is not shown. Check the connector and the wiring. There is a lot of heat in that area and something may have melted or been damaged.

Let me know what you find.

Joe

See pic below.

Image (Click to make bigger)