New here hopin for some help. I recently replaced the rear two O2 sensors, and the rear u-joint, all seemed well. fast forward a week or two, After a 40 minute drive the front end suddenly seemed to be shaking and there was a big drop in power. SES light came on and even started flashing, as I limped home at 45mph. Would only changing the rear two sensors cause these symptoms? I also wondered if the cats were clogged, there seems to be a rattling sound in the exhaust pipe that I believe is new... without looking I'm at 125,000 miles or so, on a 5.7L. Codes show a multicylinder misfire best I can recall, she's been sitting for over a month, still can't afford to send her to the shop so trying here.. Engine seems to be running smooth but I could be wrong. Thanks in advance for any help.

 

Welcome to the forum.

Really need to know the DTCs that are setting the SES lite. Most auto parts store will scan for free.

Why did you replace the rear O2 sensors?

Was the front end shaking caused by the engine shaking or something in the suspension?

 

Just rescanned, the battery had ran down,clearing any previous codes. Code P1345 is what popped up after a few seconds. Not knowing what the issue is I didnt want to let it run long to see if any other codes popped up. I think there was another before, it indicatated random cylinder misfire.

I replaced the rear sensors a while back as I was getting a code indicating an issue with sensor 2 bank 2, I believe.

The vibration/shaking is definatley from the engine as it does it while sitting in park.
Thanks

 

I should add I had three codes for some time, performance was good other than when going downhill and getting out of the throttle (it had a tendancy to sputter/hesitation you could feel, this went away as soon as getting back in the throttle.) I finally replaced the 2 rear o2 sensors, that cleared all but the 1345 code, she ran pretty good (still had the off throttle issue) until the sudden loss in performance when the misfire code kicked back up

 

With the p1345 code, would it be worth replacing the crankshaft position sensor?