Lots of codes but no solution

Hi there,
2011 sr5 214,000 miles.
It started with a drop in fuel efficiency. I decided to change my plugs. Got to my #4 cylinder plug and it was of oil… got a valve cover gasket kit and replaced that. Started it up and was running fine but now I have a CEL and traction control light. Pulled codes and this is what I have (truck is starting and running well, gas mileage is still low and feels sluggish on acceleration).
Codes:
P0390 stored
P0390 permanent
P0390 pending
P0348 permanent
P0345 permanent
P0102 permanent
Currently I have replaced with oem sensors:
Cam position sensors a and b on bank 2
MAF sensor
Both vvt solenoid on bank 2
I’m getting ready to replace all 4 O2 sensors.
The shop I take it too said they couldn’t figure out why it was throwing the code but if the sensors didn’t fix it then the timing was probably the issue or possibly a new engine. I’m not sure I’m ready to believe them. Again, it starts and runs fine except for a lag in acceleration, bad gas mileage and a very little, almost un noticeable stutter when at idle. Looking for any help, suggestions or folks who have had similar issues.
TIA,
Mike

 

Firstly, I would ditch that shop. Any shop that can't run proper diagnostics without advocating throwing the parts cannon at it isn't worth their salt. But, now that you're here, I would try an ECU reset. Disconnect the battery, walk away for a half an hour or more, reconnect the battery and drive. The #4 cylinder condition would concern me. Have you done a compression test?

 

Oil on your spark plugs may be due to worn piston rings or damaged valve seals, or it could be from excessive crankcase pressure or a failing PCV valve. This may (I could be wrong) why you're throwing so many codes. I'll ask what someone already asked.

Have you done a compression test? I bet the valve seat is worn and thus causing it to not fully seat.

 

"2011 sr5 214,000 miles" - over 200K neglected maintenance kinda record

 

Yeah. That sucks. Normally shouldn't be a problem.

 

Thank you so much for the reply’s. Every time I have replaced a sensor (which has been often lately) I disconnect the battery for long periods of time so I would think that would handle the reset. I forgot to mention. I did a compression test and these were the results.
1 - 170
2 - 175
3 - 165
4 - 165
5 - 165
6 - 175
Which from what I have read is within a good range (unless I missed something). The valve gasket is new and I have been back in and pulled the plugs and I’m not having oil in any of the plug shafts. Should I go ahead and throw a new PCV on it as a next test?

 

Not sure if our Runners have fuses for things like this, but I had an O2 code on my last truck that would NOT go away, and I changed that sucker 3x. Turns out, the O2 sensor has a fuse in the underhood fusebox, and it was blown. Man was I pissed about that lol.

Also on the same truck, I had codes for the VVT solenoid, so I replaced it. Nope. Was the actual wiring harness leading to it, got baked being so close to the engine. Bought a new pigtail from the dealer that include about 10-12" of wire, patched it in, never had a problem again.

A good scanner would be your friend in diagnosing this issue, as it is clear the shop it going to be of little help to you. With it, you can watch camshaft sensor data in real time. I didn't see you mention anything about having one, but I bought a bi-directional OBD2 cable off eBay and it conveniently came with Toyota TechStream software & license # for like $40. It is beyond priceless to own.

 

Did the CEL appear after replacing the valve cover gasket? If so, I would start looking at a wire(s) getting cut/rip/pulled out of a connector in and around the area of the valve cover replaced.

 

Yeah, all evidence is pointing towards a PCV issue. Those compression ratios are pretty damn good.

 

Another quick check would be to pull the PCV valve body and shake it…it should sound like a baby rattle. If not go ahead and replace it.

MAF sensor going out could cause poor MPG as well…and with the mileage indicated in your first post I would check that sensor as well.

I’m with the previous posts about carefully checking your work and look for any damaged/crimped/bent wiring…reseat any/all electrical connectors in the vicinity of where you were working. All it takes is a sensor wire shorting to ground somewhere that will make life miserable for the computer.

As an aside, you said the spark plug when you pulled it was loaded (full) of oil. Was the oil in/on the electrode insulator or are you observing oil on the plug’s threads only? I would run the engine (which you’ve already done after checking that plug) and go back and recheck the plug to see if it again is loaded with oil. If it is (on/around the electrode) and with the decent compression results you posted would make the valve seals suspect. If oil is only

But sometimes in the realm of what appears a complex issue, Occam’s Razor seems apropos…check wiring, electrical connections…and oh yeah, one last thing, check all of the vacuum lines! There are two in particular (about 1/2” OD) that come off the airbox…one takes a short route up to the intake manifold just behind the throttle body, on my truck that one hose had a habit of developing cracks as well as a couple other vacuum lines so carefully check them.

My prior 3rd gen also had a habit of running hot on cylinder #5 (passenger side, firewall end) but never threw codes until it hit nearly 400K, then, just prior to both O2 sensors failing the engine lost MPG (on the order of 3 to 6 mpg less). Part life expectancy is not a consistent beast and I’m sure I should have (had I known/understood better) to have replaced those O2 sensors a long time ago.

 

Bumping this thread for OP.

 

What is op?

 

You the Original Poster. It's your original thread relating to the same issues you listed in your new thread.

 

Dude don't pitch parts. Buy a $26 scan tool to reset. I been getting them sometimes. I reset and replace nothing. I started cold yesterday and shut off in choke. Next day it threw cylinder 6 misfire code. I assumed it was from not clearing the choke warning up. Reset and no more. P0430 is my nemesis usually.