2005 Grand hard start and random shut off while driving

[GTP Dad]

Based on the fact that the car shuts off when driving and will immediately restart I suggest you replace the crank position sensor. This is a common issue on GM cars and usually will not set a light in the computer until it actually fails. The SES light will illuminate indicating that the computer is performing a diagnostic. If it does not come on then the computer has not reset. Simply turn the key off and wait a few moments to see if it comes on. If it does the car should start.

[Lor411]

Hi, thank you for replying. I think I am missing a few important details that I failed to post... now that you've reminded me. When the car shuts off it is rare that I will be able to start it again from a minimum of 3-4 tries to a maximum of about 10 or so...On occasion, when it does start right away, the minute I put it in drive it stalls again. Sometimes I could be sitting there for 5-10 minutes before I am able to put it in gear without it stalling. Then I'm finally able to start moving.
sometimes I make it home...sometimes it stalls again...I have had days where it ran like new..(driving short distances...maybe 20 miles round trip) Other times I can't get it out of my driveway...but I do notice that if it stalls several times and I keep trying, I usually can make it to my destination and home without any trouble. But all of this is so random. I have tried to find a pattern but each time I think I've discovered a pattern, my theory is blown.

As you said..When the SES light comes on, I hear the fuel pump and it will start. But a lot of times as soon as I take it out of park..it stalls again. Or it will begin to start and not quite make it. Thanks for your help.

[Lor411]

Another thought I've been having is that it very possibly could be a more than one issue going on. But I think I've been trying to bury that thought...deeply!!

[thephantom1492]

Originally Posted by GTP Dad

Based on the fact that the car shuts off when driving and will immediately restart I suggest you replace the crank position sensor. This is a common issue on GM cars and usually will not set a light in the computer until it actually fails. The SES light will illuminate indicating that the computer is performing a diagnostic. If it does not come on then the computer has not reset. Simply turn the key off and wait a few moments to see if it comes on. If it does the car should start.

That do not explain why she can know before cranking if it will start or not, based on the dash light when she first put the key to run... Hence why I suspect more a power delivery issue than a sensor issue.

The park to drive also can be explained by the switch: the same switch also power the transmission solenoids. The extra current can cause the voltage to drop too much, causing an ECU reset or alike.

[danielsatur]

Anything missing on a 4-stroke motor can kill her & don't always count on Diagnostic Trouble Codes (DTC), Test's, and new parts.

Security System - ?
Air system - smoke test, map test
Fuel system - Fuel pressure test
Ignition system - Bad ground, Bat/Alternator load test, ICM test, coil, and spark.
Exhaust system - catalytic converter back pressure test

The ECU/PCU, ICM, Cam sensor, and Crank sensors can be bench tested.
Use CRC electronic cleaner + dielectric grease for clean dry connections.

If there's a history for bad Crank sensors on GM cars, that's a 1st good start.

I would put my money on the Ignition system, or fuel delivery system.

[Tech II]

My money is on the fuel pump.....keep a can of carb cleaner handy......when it won't start, spray carb cleaner into the intake.....if it starts and runs as long as you spray, it's a fuel delivery problem....either the injectors are not firing(security system) or it's fuel pressure.....

But normally, your security system will not cause a stall, so I'm guessing the fuel pump......so check check the fuel pressure with a gage when IT WON'T START....

[danielsatur]

That's probably the best test to see if it's the fuel system or ignition system.

[Lor411]

Thank you all once again. I did have the pressure checked - that was the first or second thing I had my mechanic do. He had to wait until it wouldn't start..first couple of times I took it to him it would start up every time of course. He told me the pressure was right up to specs. But I can have him check it again.

As far as the security issue, here's something you may want to know.. I only had one set of keys so I went back to the dealer to ask him for the second set. He told me there wasn't one. I told him that this car and year comes with a Passlock system which is standard...He said no it doesnt...Of course he was lying.

My key does not have a chip in it. But the thing is the security light never flashes, nor does it stay on.
every forum I've read on the issue those 2 things happen when the security is messing up.

I don't know if this will help, but I will tell you exactly the order of things as they happened, maybe you can get something out of it.

Very first thing: One day my key got stuck and would not turn. I was parked on a slight incline.
I jiggled it for a while, made sure my shift was all the way in park..I eventually got it to turn.

This happened for about a week. Then that stopped totally.

Next. I could not get the shift out of park..That happened only a few times, then stopped.

Next..I was driving at night in the fog with my flashers on..My husband swears I left them on over night..I know I did not..Battery was dead in the morning. Got a new battery..all was fine.

One day...I go to the gas station and filled up my tank...after that for the first time EVER...my car would not start..right there at the gas station.. I thought it was bad fuel. Over the course of a couple of weeks, it began to not start randomly...That was the problem for a while..

Then for the first time ever...I shut off while driving..Never had the key get stuck ever again...never had the shift stuck in park again...Battery has been fine.

So the starting and shutting off has been that way for about 4 years now....And the past 2 weeks it seems to happen more often..But could be because I work from home and I don't drive it everyday...I don't know.. sorry Im rambling on, but maybe this info will help.

All I can say is I just hope All of you aren't right!! But that WOULD be my luck.

Thanks again!

[Lor411]

Originally Posted by thephantom1492

That do not explain why she can know before cranking if it will start or not, based on the dash light when she first put the key to run... Hence why I suspect more a power delivery issue than a sensor issue.

The park to drive also can be explained by the switch: the same switch also power the transmission solenoids. The extra current can cause the voltage to drop too much, causing an ECU reset or alike.

When the SES light comes on, I hear the fuel pump priming at the rear of the car passenger side, every time, and I wait until it the pump stops before I try to start it. When the light does NOT come on, the pump does not prime and the car does not start.

[Tech II]

Grand Am's do have PassLock......it uses a blank key.....can get one made at any hardware store(get one now before you lose the key)....the key is not your issue, as long as the lock cylinder turns(usually when it's hard turning, it's the tumblers in the lock cylinder, or it's because the way the wheel is turned when you remove the key)....

As for PassLock, you can have a problem, and the SECURITY light might not flash....only way to know for sure is to have the vehicle scanned for "BCM" codes....usually you will find a B2958 or B2960 set.....many garages/auto stores do not have scanners that can read BCM codes....

[rkvons]

Next time you get your car running and have a couple of spare minutes, pop the hood and carefully start wiggling the wires to your ICM. There is a two wire connector on it to a Cam Position Sensor on the back of the engine. Make sure this wire and its connector is dependable. If the engine dies while you are messing around in that area, you're on to something.

[Lor411]

Originally Posted by rkvons

Next time you get your car running and have a couple of spare minutes, pop the hood and carefully start wiggling the wires to your ICM. There is a two wire connector on it to a Cam Position Sensor on the back of the engine. Make sure this wire and its connector is dependable. If the engine dies while you are messing around in that area, you're on to something.

Thank you...will do that and let you know!

[Lor411]

Originally Posted by Tech II

Grand Am's do have PassLock......it uses a blank key.....can get one made at any hardware store(get one now before you lose the key)....the key is not your issue, as long as the lock cylinder turns(usually when it's hard turning, it's the tumblers in the lock cylinder, or it's because the way the wheel is turned when you remove the key)....

As for PassLock, you can have a problem, and the SECURITY light might not flash....only way to know for sure is to have the vehicle scanned for "BCM" codes....usually you will find a B2958 or B2960 set.....many garages/auto stores do not have scanners that can read BCM codes....

Thank you! I often wondered if there could be a security issue even though there were no symptoms with my security light. In fact. I initially suspected that the starting issue and stalling issue could have been 2 separate things. I will look into the PassLock thing as well. Much appreciated.

[Lor411]

Originally Posted by thephantom1492

I have the procedure, I'll type it out later in detail...

basically, disconnect battery negative. Remove the instrument cluster, which should be: remove the 2 screws under the steering, remove the top cover, burried behind you have 2 screws for the IC trim, plus 2 on the top, remove trim. remove the screws for the IC, remove IC by noticing how you remove it (it slide in/out one way, easy to figure at removal, harder at insertion time). Remove ignition switch, relocate to an easier to access, put key to run, press and hold the button under it (metal tab/pin), pull the key... the rest should be easy...

will write more in detail later today

Hi Phantom! My mechanic can't get to my car until Oct 2nd..Can you post the details for the switch removal and replacement, if you could? Also, I have searched everywhere for more information on the procedure but the instructions are how to replace the lock cylinder from behind the radio...nothing on how to remove and replace just the switch from the instrument cluster. Can you help? Do you know if the procedure for the 2005 v6 is the same as 2003-2004? Thank you!!

[Lor411]

Originally Posted by thephantom1492

I have the procedure, I'll type it out later in detail...

basically, disconnect battery negative. Remove the instrument cluster, which should be: remove the 2 screws under the steering, remove the top cover, burried behind you have 2 screws for the IC trim, plus 2 on the top, remove trim. remove the screws for the IC, remove IC by noticing how you remove it (it slide in/out one way, easy to figure at removal, harder at insertion time). Remove ignition switch, relocate to an easier to access, put key to run, press and hold the button under it (metal tab/pin), pull the key... the rest should be easy...

will write more in detail later today

Hi again, forget about the instructions for now..I took a look and on my car there are 3 screws under the steering wheel and they are torx screws. Anyway, i will wait for Oct 2, that way I can have the mechanic test a few things you guys mentioned as well. Thanks