Chevy Malibu Need help with dtc P16do rocker arm lift solenoid , dtc keep coming back
1G11B5SL7EF275672 I have the dtc mentioned above for this 2014 Chevrolet Malibu 2.5 l , (that is the only dtc present) , customer needs to pass emission test to registrar vehicle . current miles 107,368 history in our system appears this customer brought this vehicle to us by firs time with this dtc when it was 40 k , we advised to take to dealer for warranty .He did, they replace the intake rocker arm solenoid pack , dtc returned he took it back they replace updated rocker arm he said , dtc keep coming back , he brought it back to us , we have seen in our history about 5 times this vehicle for this dtc over the years. oil level and conditions are good at all time any way we recommended to do oil flush with BG moa , and also show we replaced that solenoid too with dealer part , and about 2 months ago customer took it back to dealer in preparation for smog, they replace the solenoid again with no succeed how ever the light is still on same dtc he is back again with us , as today he brought me that for smog test of course I have to repair the check engine light on first, I recorded the dtc and freeze frame data , clear dtc and I took it for road test to find out how often the dtc returned also I was monitoring data relevant to rocker arm solenoid pcm command is sent out no circuit codes . in about 9 miles the dtc returned, there is the setting criteria as well the description and operation of the system.
I am doing some scope test , using the oil pressure switch signal .
I connected to the power feed to solenoid the low amp current clamp channel A , engine running at idle warm ,I activated manually the solenoid 1 and 2 , channel B is for oil pressure transducer signal.
when I energized the good working system for solenoid 1 I can see there are changes in oil pressure
when manually energizing solenoid 2 system with dtc, no changes in oil pressure
there is also a tsb we have not performed I believe this is the first time for me working on this vehicle. according to identifix repairs hit no body has report to have fix it with tsb there are all of them reporting faulty solenoid fix it.
any advised is welcome I appreciate your help .also I included the pico scope file , the first screen is for solenoid 1 with known good system , the screen 2 is for the system with fault solenoid 2 testing .
Your testing was excellent. Looks like you have an oil pressure issue. I'd be following that bulletin first. Also you have good pintle bumps on both solenoid current traces. This is definitely mechanical it looks like to me.
thanks, mechanically seems they are operating , the oil pressure is not getting to the rocker arm to lock the pin is my theory . does any body has performed this tsb ? timing cover needs to be removed, I do not know about timing gears
Never done the bulletin. However the cover and timing is cake on that engine. Just follow SI like any other vehicle.
Good Stuff, just to make sure you are taped at the cylinder head oil pressure sensor BLK/BRN wire? Before taking the timing cover off, do you have a pressure transducer that you could connect to the cylinder head oil pressure switch port just to see the actual oil pressure?
yes I do have pressure transducer
The previous rocker arm solenoid may have come apart and blocked the oil passage in the valve cover. Refer to PIP5527D and picture below.
I will definently check that area
That is great information just came out that tsb
Hi. just curious, how did it turn out?
Yesterday I got it finish today I will be updating the info, I install new valve cover and new solenoid pack( per 1 tsb) second or previous tsb to removed front timing cover and replace plug seal I did not applied that, I did not doit. and retake the waveform, road tested vehicle many miles , but yes now my oil pressure changes when I manually activacted the solenoid 1 and also solenoid 2 . I…