[graymatter]

I have a 2011 Malibu LTZ with the 3.6 V6 and automatic 6 speed. It has about 135,000 miles on it and I recently had to replace the alternator, serpentine and starter all within 24 hours… The car is running better than ever except for one odd issue; now when I try to start it remotely, it will only run for a few seconds and then shut down. I found this old thread:

remote start dies after starting

2009 Malibu LTZ ever since I changed my alternator my remote start will start the vehicle then it dies and won't remote start again I have a 2009 Malibu LTZ and when i USE THE REMOTE START IT DIES AFTER A FEW SECONDS

www.chevymalibuforum.com

But it is closed to further comment. I’m just wondering if anyone reached a permanent solution for this issue. I’m guessing that the voltage inputs have changed so drastically that I need to re-flash the BCM or ECU? Anyways if someone could point me in the right direction I would be very grateful. Thanks!

 

[repairman54]

Check engine light on ? Any codes ? If any codes are present, it may start and stop or not start at all. Needs a full scan of all 4 code families not just P codes.
For example, if a door lock isn't reporting it's locked it can affect remote starting.

 

[graymatter]

Check engine light is not illuminated at the moment. It was working perfectly fine until I replaced the alternator, and no new codes came up afterwards. I have one of those simple and cheap obd2 readers so I will do a check when I get home and let you know what I find.

 

[graymatter]

So I’ve been unable to find any codes… another strange symptom seems to be happening intermittently along with the 3 second remote start. Every so often while I’m driving the check battery light will illuminate. If I go and meter out my battery and alternator leads, it will read somewhere around 12 or under; sufficient for the light to come on. So it mimics a bad alternator, but all I need to do to bring it back to life is disconnect and reconnect the battery. So I’m guessing something in the voltage regulator system? I’m at a bit of a loss here… 🤔
2011 3.6 LTZ
New battery
New alternator
New serpentine
New blower motor
New temp sensor
Synthetic oil change every time the life reaches 25%

 

[graymatter]

So upon further investigation, there are a few main symptoms that should point to a common problem. Obviously the remote start issue; it holds a start briefly but shuts off after a few seconds. Then every few days the battery light will illuminate while driving. I’ll get out and test the voltage at the alternator leads and read 11.5 ish and going down. If I shut off the car and disconnect the battery for a minute or so, it will start up just fine and run like a dream until it happens all over again…. If I allow it to run long enough with the battery light; the gauges will go haywire and the car will die - but start up again after a battery reset. I’ve scoured some other posts on similar issues and have come down to either a grounding issue or perhaps a problem with the BCM? Or perhaps there is some sort of intelligent charging module that has gone bad?

Can somebody tell me where the grounding points are on a Gen 7 3.6 litre LTZ, or anything else I can look into that might work? Thanks!

 

[repairman54]

Was it a new alternator or a reman. one. Remans are not reliable if not done by a local independent rebuilder. Many folks have had issues with Cardone reman. units for example. They do remans for most of the big box stores and their brands.

 

[graymatter]

It was an ac delco reman, but from a reputable distributor in Canada complete with bench tests. The alternator works just fine, until suddenly it doesn’t…. That’s why I believe it comes down to whatever module/computer that’s responsible for intelligent charging functions, or perhaps a shoddy ground connection somewhere. It will run fine for a few days until something is triggered and the battery light comes on. I disconnect the negative for 60 seconds, hook it back up and she starts right back up with the light cleared. Here is a broad picture of the symptoms I’ve been seeing:

1. The alternator charging issues
2. My starter crapped out RIGHT after I put in the new alternator
3. Every now and then I get the SERVICE ESC/TRACTION CONTROL OFF bombardment of messages (usually in reverse)
4. Remote start works, but won’t hold for more than a few seconds

there really seems to be some sort of voltage misinterpretation happening in multiple systems…