Misfiring what are my next steps

[jphil]

I’m sure this is covered a lot here as the 2.4 is notorious for many reasons.

I need to be able to lay out all the info I got and get some wisdom on next steps. My 2011 2.4 equinox is misfiring and basically undriveable. Here’s my history:

2011 equinox lt 2.4 178k miles

Bought with 145k miles
145k - New spark plugs, coils, both of those solenoids on top of valve cover (all just preventative new purchase maintenance)
146k noticed that it burns oil. Shocker!
Since 146k - change oil ever 3k miles with full synthetic high mileage oil
155k P0420 code - replaced cat converter and exhaust manifold (was cracked)
Ran great until 170k
170k started idling rough. Cleaned throttle body and seemed to help it out a lot
174k new valve cover gasket
177k code P0138 - replaced both o2 sensors and code went away but came back on 300 miles later
178k starts misfiring and surging, code P0138 and P0300.
Parked it and can’t drive it now.

Have done a bunch of research. Don’t know what to do next. On a major budget I do not want to take it to a mechanic and I also don’t have diagnostic tools aside from the code reader.

Thoughts?
Clean fuel injectors?
Check for air leaks?
High pressure fuel pump?
Timing chain issue?

I know the oil buring is bound to eventually ruin it. And maybe it now has. I’m not having the piston rings done, the car isn’t worth it.

What should be my next steps? Thanks!

 

[kpmueller2006]

Hi, I have a 2015 2.4 equinox. I wasted a lot of money buying sensors with no noticeable changes, this includes throttle body, both fuel sensors and fuel pump, and it goes on
What I finally did have done is my timiming chain and all related parts. Not only was it 100 times better it doesn't die or go into limp mode anymore and all codes are gone!!

 

[pappyl]

You have 2 different codes here
- p0138 indicates probable O2 sensor failure
- this can be caused by running really rich from a bad injector - usually screws your cat however, or its an aftermarket shit injector

- p0300 is most likely spark over bad fuel injectors, but...
- ALWAYS pull the plugs and inspect they can tell you at lot to what is wrong
- check coils and replace plugs (probably bad coil - probably caused by bad spark plug) - can use an inline spark connector, mulitmeter ohm check

- if spark OK, pull the fuel rail and test injectors (need to pull off intake housing - not too hard, may have to push the AC lines toward rad a bit, be careful, DO NOT pry on the fuel rail to get the plastic intake off, can damage injector plugs, etc. Make sure you get the lower bolt off the oil dipstick connector plate.

As per above, do you have any chain rattle going on? Pull the cam cover and check if chain is tight, any wear signs of a floppy chain. If either, agree to change that timing chain asap.