P0201, P0203, P0205, P0207, P0300

[prfrmr3]

I purchased my 07 5.3 LS back in June.  Over the summer I started getting intermittent P0201, P0203, P0205, P0207, and P0300. Along with those codes I am also getting messages saying Service Stabilitrak, Service ABS, and Traction Control Off.  This seems to come and go on a whim.  I can be driving down the highway and it will hesitate then throw the messages and codes. Of course when it does it runs incredibly rough and is WAY down on power. Then, sometimes immediately, sometimes 30 miles later, sometimes the next day all of the sudden the power comes back and everything clears on it's own. I have had it to a mechanic, and of course when they go to work on it they can"t get it duplicate the issue. They tell me to bring it in as soon as it does it, but I can never seem to make that happen when they are open. I have also noticed that at idle all of the lights interior and exterior will pulse (whether the CIL is on or not) but when under power it goes away. Has anyone else experienced these problems? It is incredibly frustrating not to be able to track it down.  I LOVE my Avalanche and it is driving me crazy that I can't seem to figure this out.  I would be incredibly grateful for any insight and thanks in advance. 

 

[Randy]

Since the codes are P0201, P0203, P0205 and P0207 which would point to the right side (driver/bank 1) injector problem, the P0300 is multiple misfires caused by the injector issue.

So I would start with the injector wiring harness the right side. It could be a bad connection, ground or a short. I've seen mice chew up a harness on more than one car and a few here have posted similar issues with the little critters.. I opened my hood one time and a mouse was sitting on the valve cover and leaped right by me and scared the crap out of me.. Looked all over for any signs of chewing, didn't see any and have never had any issues (knock on wood)..

Good luck

 

[Mr.G]

in February 2020 I started having a random hot starting issue when my 07 sat any longer then an hour after driving as little as 10 miles it did not want to start, would do what the service department was calling a long crank, well after having it at the dealership 3 times in 5 months and still not fixed and a new crank sensor, ECM, plugs and coils, not to mention about 6 cleaning including some kind of soaking to clean the valves they said they were not closing all the way and this could be causing the issue.

Any way when I picked it up last Wednesday I had a Stabilitrak and traction control light on my dash told the service adviser and he cleared the code and said all was good. on the way home the light came back on and then went off again, was told by service adviser to put a higher octane fuel in, so I did. We took a long trip this week end and the Stabilitrak and traction control light kept coming and then going off after about two miles, I would also get a P0173 and P0175 CEL code at the same time no issues with running or anything. except that the dumb Stabilitrak and traction control light kept going on and off.

I'm going to try to contribute the P0173 and P0175 to the cleaning they did unless it does not clear up after a tank of gas.