• The site migration is complete! Hopefully everything transferred properly from the multiple decades old software we were using before. If you notice any issues please let me know, thanks! Also, I'm still working on things like chatbox, etc so hopefully those will be working in the next week or two.

Car shuts off when pressing gas

Grandprix2007

New member
Hello, I own a 2007 pontiac grand prix with the stock v6 motor 100,000km on the odometer and when I was driving today and went to press the accelerator to complete a turn, the engine and the whole car completely shut off on me while still in drive. The car starts up fine ( Has 2 month old battery) and idles okay, but when the rpms are low like when coming to a stop when I press on the accelerator the whole car just shuts off, and I tried to restart it about 5 times before it finally would accelerate in drive (reverse works fine as far as I can tell). I had a full tank of gas but does anybody know what the problem could be? Thanks for the help.
 


check fuel pressure.

if you dont have a gauge after it stalls out leave the key to run pop the hood, hit the pin in the shrader valve on the rail. if nothing comes out the fuel pump is bad.
 


Hello, I own a 2007 pontiac grand prix with the stock v6 motor 100,000km on the odometer and when I was driving today and went to press the accelerator to complete a turn, the engine and the whole car completely shut off on me while still in drive. The car starts up fine ( Has 2 month old battery) and idles okay, but when the rpms are low like when coming to a stop when I press on the accelerator the whole car just shuts off, and I tried to restart it about 5 times before it finally would accelerate in drive (reverse works fine as far as I can tell). I had a full tank of gas but does anybody know what the problem could be? Thanks for the help.
When it shuts off, does the engine light come on?

I have a 04 Pontiac Grand Prix and had a similar problem. I'll be driving and once I go over 35 or 40mph it'll shet off. I can't really remember how I fixed the problem but the main thing I do remember is that I replaced the gas peddle. That can go bad as well.

Sent from my SM-N950U using Tapatalk
 
when it stalls every dummy light should likely come on.

dbw pedals do go bad, could have a pending code for that, if you have a scanner, scan it after it stalls, dont turn the key off or that code could clear.
 
I am not sure how to measure that.

Rent a fuel gauge from autozone or buy one from harbor freight, hook it up and look at the readings at key on engine off, when removing the vacuum line to the regulator, with the car running, and when you open the throttle. That will usually tell you how the fuel pump is performing and would be an easy way to start without having a scan tool to measure the fuel trims.
 
Acceleration Peddle Position Sensor (Gas Peddle), that's what it was. I also remembered replacing my throttle body because 'Reduce Engine Power' will pop up on my dash. Went to the Junk Yard for both items being cheap. But it worked ha

Sent from my SM-N950U using Tapatalk
 
I know very little about cars so where is this valve located?

fuel rail rad side of the engine, theres a fat black cap, take i toff, wish a small screw driver hit that pin, if you have good pressure its gonna spray every where with force, no pressure nothing comes out but a dribble. watcher yer eyes, use a rag over it to keep the spray at bay.

pressure gauge would screw on at that same location.
 


When it shuts off, does the engine light come on?

I have a 04 Pontiac Grand Prix and had a similar problem. I'll be driving and once I go over 35 or 40mph it'll shet off. I can't really remember how I fixed the problem but the main thing I do remember is that I replaced the gas peddle. That can go bad as well.

Sent from my SM-N950U using Tapatalk

No lights that I can remember, but I just took it for a drive and everything worked perfectly, could it possibly be something in the fuel causing a stall?
 
Ok thank you very much for your help, I just took it for a drive and everything worked perfectly so it seems like an isolated incident, could something bad in the fuel cause a problem like this?
 
I am sorry but I have no idea how to do any of that but it seemed like an isolated incident so could something in the fuel have caused that or should I just take it to a mechanic who knows what he is doing.
 
if this was one time deal id be thinking crank sensor going bad. when they fail the car just stalls for no reason, one tell tail sign is the tach will stop working sometimes, it also might quit working right before it stalls too, its hard to notice that happen tho.

and if your not up to finding a fuel rail shrader valve you need a shop to change that sensor, harmonic balancer needs to come off to get to it.
 
I am sorry but I have no idea how to do any of that but it seemed like an isolated incident so could something in the fuel have caused that or should I just take it to a mechanic who knows what he is doing.

I highly doubt it's an isolated incident and unless someone is dumping some pretty toxic into the gas where you are, it won't cause this. It will happen again. Unfortunately, be prepared for a heafty bill, since they're going to charge you $100+ an hour for diagnosis, plus the fix, and most likely they won't find the correct fix the first time. I was quoted $800 for the sensor replacement.

If you want to save yourself some money, and learn and have fun fixing your own car, then strap in and grab some basic hand tools. All the "special tools" you need to fix this you can rent at autozone. I'm not a fan of replacing the crank sensor unless you know that's the issue, but unfortunately, you need a scan tool to really do that.

Reason I'm recommending starting checking the fuel pressure is that it can cause these symptoms, it's incredibly easy, and you can rent the tool for free. From there, I'm with Scotty.

There's tons of videos and tutorials on how to change the sensor and it's really not that hard, and it'll save you a ton of money. Four years ago, I couldn't change my own oil, since then I've done almost every repair imaginable and taught myself to rebuild engines and transmissions and I did it without anyone physically there and most of what I learned came from Haynes manual and youtube. Trust me, anything is possible.

That being said, no one here will judge you if you decide not to fix it yourself, just know we're all here if you need help and decide to troubleshoot it yourself. Good luck either way!
 


I highly doubt it's an isolated incident and unless someone is dumping some pretty toxic into the gas where you are, it won't cause this. It will happen again. Unfortunately, be prepared for a heafty bill, since they're going to charge you $100+ an hour for diagnosis, plus the fix, and most likely they won't find the correct fix the first time. I was quoted $800 for the sensor replacement.

If you want to save yourself some money, and learn and have fun fixing your own car, then strap in and grab some basic hand tools. All the "special tools" you need to fix this you can rent at autozone. I'm not a fan of replacing the crank sensor unless you know that's the issue, but unfortunately, you need a scan tool to really do that.

Reason I'm recommending starting checking the fuel pressure is that it can cause these symptoms, it's incredibly easy, and you can rent the tool for free. From there, I'm with Scotty.

There's tons of videos and tutorials on how to change the sensor and it's really not that hard, and it'll save you a ton of money. Four years ago, I couldn't change my own oil, since then I've done almost every repair imaginable and taught myself to rebuild engines and transmissions and I did it without anyone physically there and most of what I learned came from Haynes manual and youtube. Trust me, anything is possible.

That being said, no one here will judge you if you decide not to fix it yourself, just know we're all here if you need help and decide to troubleshoot it yourself. Good luck either way!
Thank you very much sir, I would try to fix it myself but I am busy with my university studies and dont have much free time. Luckily I know a mechanic that is a family friend that shouldnt charge much but I definetly want to get it fixed as stalling right in the middle of an intersection scared the crap out of me. Thanks to everyone who helped out on this thread.😁
 
Thank you very much sir, I would try to fix it myself but I am busy with my university studies and dont have much free time. Luckily I know a mechanic that is a family friend that shouldnt charge much but I definetly want to get it fixed as stalling right in the middle of an intersection scared the crap out of me. Thanks to everyone who helped out on this thread.

No problem! I completely understand. I'm taking full time courses in engineering and working a research assistant job at my university so I understand being busy! It's always good to have a good mechanic in your corner. After everything I've done, there's still some issues that I have to default to a mechanic (usually because I don't want to buy a $3000 scan tool...). Even though you're getting this problem fixed, I encourage you to stick around! This forum is a lot of fun for both people who know a lot, or people who are just starting! Plenty of ideas to take up your free time! :D Good luck and please post what the solution was so that others can learn too!
 
Back
Top