hello,
been reading up on a problem I’ve had with my TL. 2010 6 speed manual 140k
after getting some paint touched up, the body guy let the vehicle sit on a hill overnight. When I picked it up I got the so-called Christmas tree lights of hill assist, emissions, vsa, and check sh-awd. The car seemed to drive fine. After clearing the codes, all has seemed fine the past few weeks. I chalked it up to maybe a low battery charge or because it was parked on a hill overnight.
Today all the lights came on again as I was exiting a slow decline Parking lot.
The codes exactly are p0300, p0304, p0305, p0306 and all wheel drive 77 and vehicle stability assist 83.

the spark plugs were changed by me about 3000 miles ago, and the timing belt about 4000 ago by a local shop.

I have been thinking it’s time for a valve adjustment as it seems to be slightly noisy. Could too tight valves be causing the misfire codes? Coil packs maybe since the codes seem to be on one side?

So hooked up the scanner and still showing misfire on cylinders 4,5, and 6.
it also showed a pgm-fi malfunction and a clutch pedal switch b malfunction 118-01.

The plot thickens.... I’m going to inspect the wheel sensors and replace the egr valve.

Both the battery and alternator passed their tests with a voltmeter, but feasibly it could be a bad ground somewhere. Not sure where to even start looking to track down a bad ground

Battery

Battery seemed to test fine and is less than a year old

So I think the ground issue has been solved..... drove and no issues so far

As it turned out, it was the fuel injectors, not a bad ground.