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Hi, I'm Dave
I can try to assist you with your problem here.
I cannot "diagnose" your vehicle over the internet. There is also no way to tell you what to "fix" without first diagnosing the problem so it can be determined what, exactly, needs to be fixed. What I can do is tell you what needs to be done to get this diagnosed so you can get it repaired.
First, I can tell you that your "Passlock" system is NOT causing your stalling. The Passlock system will keep the engine from starting if the correct (programmed) key is not used to try to start the engine. However the Passlock system will not cause the engine to stall once it is already running. If there is a problem with the Passlock while the engine is running, the "THEFT" light will be illuminated, but the engine will continue to run until it is turned off with the key.
Your best bet would be to scan your onboard computer network for possible fault codes. There are literally HUNDREDS of different circuit failures that can cause the engine to stall. There just may be some computer information stored in the computer memory that will cut through all the "guesswork" and point you in the right direction.
This is what I really recommend that you do for starters.
Otherwise, the symptoms you are describing are consistent with a crankshaft position sensor that is giving up the ghost. These are known for causing intermittent stalling and are a fairly common failure. Please understand that I do not know for sure what is causing this because there is no way I could possibly know that without proper diagnosis, but I hope this at least gives you a direction to look in.
Let me know if I can assist you further.
I will look into the crankshaft position sensor. The issue is supposed to be repaired by the used car lot we bought it from, but since they have no clue what they're doing I figured it couldn't hurt to reach out for ideas.
Their next big idea is they're currently replacing the fuel filter even though I highly doubt that is the issue.
Would the crankshaft position sensor be setting off the "security" light on the dashboard though? That lighting up is what lead me to believe the issue was with the passlock system
Thank you for your reply John,
No, the fuel filter is not likely to be causing it....But that should be done as normal maintenance anyway, so if they are not charging you for that, it is not a bad thing...The previous owner probably never changed it.....most people don't think about those things until the car quits running. (Keeps me employed)
Is the SECURITY light coming on while you are driving the vehicle?
If so, you DO have a problem with your Passlock system - however, this is still not the reason it is stalling. If a failure in the Passlock system occurs while the engine is running, the engine control computer (VCM or PCM) will become "Fail Enabled" - meaning that it will be allowed to operate the engine even though the Passlock system has a failure. However, the SECURITY light comes on to let you know that there is a failure in the system so you will know that you need to get it fixed. Any time your engine computer is "Fail Enabled" it is NOT protected from vehicle theft. It is like the antivirus on your home PC getting turned off....The computer works, but is not protected from hackers and thieves....
Also, if the computer is in fail enable mode and the system has an active fault, if the battery runs down or is disconnected for any reason, the engine will not start when the battery power is restored. The Passlock system is controlled by the Body Control Module (BCM). The BCM will only allow the VCM or PCM to operate in "Fail Enable Mode" as long as the BCM has battery power to "remember" that it is allowing this. Once battery power is lost, it loses its memory and starts over.
I get customers all the time that do not understand when I tell them that their engine is now not starting because of their Passlock system after they changed their battery. The say "The SECURITY light has been on for YEARS....Never had this problem before!!!" This is because they do not understand how this system works.
Download the PDF file HERE
Please note this file will be deleted in a few days due to copyright restrictions.
This file will explain this a little more for you.
The security light only comes on only once the car stalls out. then i wait about a minute restart the car, and then soon as it goes to shift to a higher gear while driving it shuts right back down.
I'm trying to just get our money back for the car, but the used car lot is saying well the paperwork is already processed it cant be reversed. This has just been more of a headache in a months time than any car I have previously bought.
That would be a good question for one of the legal professionals on this site. Many states have laws governing issues like that when it comes to buying used cars. I have lived in several states and some of them are strictly "buyer beware" when it comes to used cars. A couple of them had consumer protection laws stating the vehicle can be returned to the dealer within a certain period of time (regardless of whether any paperwork has been "processed") for a full refund in cases like this.
I am not a legal professional. I cannot advise you on this other than to advise you to get legal counsel to see what recourse you may have in the area you live in. I would advise you to seek this legal counsel immediately, because your options may be very limited by time - maybe 60 or 90 days.....the dealer may be simply "stalling" you in an effort to make this time run out - if this applies to your case.