1999 Pontiac Firebird Stalling

Ok I don't think it has much to do with putting gas in the car. Does it do this any other time? I am thinking that maybe the time it sits as you get fuel that it cools just enough that the coolant temp sensor is not reading correctly and could be causing this. Also do you smell any fuel like a leak? Also you could put some Seafoam in the tank to see if it may just need some cleaning. Get back to me.

No, the car does not stall any other time. If it was the coolant temp sensor, then wouldn't it stall out in the morning and when I run into a store for a little while. I do not smell any leaks either. I did put in STP Fuel Injector Cleaner but this did not help either. It was doing it before and still does it after going through a full tank with STP. The guy at Autozone told me, when I bought the gas cap, that it could be the fuel level sensor. That maybe it was registering wrong after putting fuel in. Like it tells the computer that I'm out of gas and not that I have more. Then it levels out properly and stops stalling. Does that sound plausible? Thank you for your help by the way, I do greatly appreeciate your time, especially if we can figure it out...lol. :)

Ok no Autozone's idea don't make any sense as the there is no fuel level sensor. There is a sending unit but it don't talk to the computer on the gas guage. I will be asking some questions to try to help figure this out so bear with me. As for the coolant sensor that is correct that is why I asked if it does it any other time. Now I do have another question what does the oil pressure do? What I mean is when you start it does the oil pressure come up and when it does, does it stay up or drop just before it dies? Does it start right back up or does it need a minute or two before it will start again? Do you have the means to check the fuel pressure? If so then you could hook up the fuel pressure tester and go get gas and see what the fuel pressure does as you turn the key on and as you start it and when it dies. Get back to me with what you know and what you can do and we will take it from there.

Ok...I will check the oil pressure gauge the next time I get gas (later today or tomorrow morning) and let ya know.

The car does start right back up, I don't have to wait to restart.

I don't have a fuel pressure tester but I can get when if you think I will need it. If I don't really need one, let me know. would rather not spend the money if I don't have to.

Ok...I went to get gas this morning and checked how the oil pressure gauge reacted. After fueling and starting the car the oil pressure went right to 60 then the car started coughing and then the oil pressure dropped. The oil pressure did not drop first. It dropped the same time or a fraction of a second after stalling. I started it again, didn't have to wait, it started right up and it did the same thing. Up to 60, car coughed, pressure dropped as it stalled. Does that help you at all?

OK that tells me that the oil pressure sender is working ok so now I would like to know what the fuel pressure is doing when it stalls. I have never had a car do this before in all my time wrenchin so bear with me we will figure this out. I would like to know when the last was the last time you replaced the fuel filter? I also would like to know if there are any performance mods and if so what? The more info you can give the better I can help. Also when it starts back up do you get any black smoke out the tailpipe?

Ok...next step...lol :) I guess I will have to get a fuel pressure tester to let you know what it is doing, huh? No problem. It might take me a couple of days to pay for one though.

I have never replaced the fuel filter though. I just got the car about 6 weeks ago, used so I might have to do that.

What is a performance "mods", oh wait...you mean modifications. No there are none. It is all factory. Nothing added to it.

No there is no black smoke either. This baby runs so smooth I was amazed myself. It is the first used car I ever bought and had serious concerns. I got the carfax and it has had only seven owners and the only time it has been to the shop was for regular maintenence. She purrs, except for when I fuel her.

So you think I definetly should get the fuel pressure tester? Let me know and I will get one.

Thank you for time time. Seriously!

Rob Reiss

Ok that will work. I would replace the fuel filter however so you know when it was done last. GM has a very tight media with there fuel filters so I recommend once a year replacement. I have done all kinds of performance mods on my car. I also enjoy racing. Anyway just something on the lite side thats all. Get back to me with what you find. Don't spend a lot on a tester you only need one that will do your car so more the 50 bucks is pushing it.

Hey....whats up? I already replace the gas filter. I used your web-site and folled instructions. They were perfect. Filter was under drivers-side just infront of rear tire....no probs...seems to be running a little smoother. Haven't put more fuel in yet though. I did have one prob after replacing the filter. When I went to start the car, the bat died instantly. Had my neighbor give me a jump and no more prob. I think it was cause since there was no fuel in the line the electronic fuel pump along with electronic fuel injecters killed the bat before the fuel was able to travel through the line. Does that make sense?

Will get a fuel pressure tester in the next few days. I found that most are between 19.99 to 29.99. Thats cool with me.

Thanks for your time. If you have any suggestions or comments about what I did and the bat loosing juice, let me know.

Ok sound good maybe you should get gas before buying a fuel pressure tester? As for the battery have it tested it may be weak and able to hold a load better to check now then to find out when it gets cold one night and you can't start it the next morning. Let me know how it goes.

Ok...I got gas and it is still stalling even with the new fuel filter. As for the battery, yeah that sucker should have never been in this car to begin with. Was to small and was gonna die soon anyway. Went and got the proper size for my car and have no starting problems but still is stalling after I get gas. So, what's next dude?

Ok well now we need to know what the fuel pressure is doing when this happens. It may be that it isn't building up fuel pressure or holding it. I would find it strange to be a fuel pump but can't rule it out yet. So what you need to do is hook up the fuel pressure guage and let me know what it is before you turn the key on and what it is when you turn the key on and what it does as you crank it. Also if you can let me know what it is as it is running too.

Ok..check it out. I just went to go take my wife to work and noticed it stalling now when I take turns. I turned out of my parking lot and it bogged down, went straight down the road, no prob. Turn into her place and it bogged and stalled. Started right back up. Turned out of her parking lot, it bogged. Went straight, no prob. Turned back into my parking lot, bogged then stalled. Does that mean anything different now. Also check out these photos of the engine coolant dip-stick. This can't be good.

Check the oil too. This looks like there is oil in the antifreeze and I am hoping that there is no antifreeze in the oil. Include a pic of the engine oil dip stick too please. Thanks.

Noprob..will take the pic tomorrow, but I just checked the oil and it is clean, unless you can see something that I don't know to look for. I'm starting to think it's the fuel pump. When I changed the fuel filter, I didn't depressurize the line. The gas in the line just dripped out. Shouldn't there have been pressure in it?

Yes it should have had some pressure so I would agree with the fuel pump suspitions. Now as for the engine coolant did you mix red with green antifreeze? If so then you you will need to clean and drain and refill I would use green antifreeze once it is flushed. Now I would also like to know if this is an auto or stick? If auto check transmission fluid too. If the oil doesn't look like chocolate milk then no worries there.

I never did anything with the coolamt/antifreeze. When I pulled that di[stick, that was the first I ever looked at it. I took a pic of my oil dipstick and the radiator without the cap on so you can see. The transmission fluid is nice and pink/red. No probs there. Let me know if ya think I sould still flush the radiator. But I thin k the stalling is definitley the fuel pump. I take it you agree?

Ok I would say everything looks good except the antifreeze. I would flush it and change it, it looks like it needs it as it looks like someone has mixed antifreeze colors and I would use the green. This isn't related to you running problem I still think that fuel pressure needs to be checked as I am leaning toward the fuel pump on that problem. On the transmisson fluid is that more orange then pink? Hard to tell in the pic. If it is more orange then it is due to be changed too. Let me know how it goes with the fuel pressure check.

Yeah, I'm gonna flush it just to be on the safe side. Already got some Prestone radiator flush I'm gonna put in later, then gonna refill with the Prestone grenn 50/50. As fore the stalling, funny thing. One of my wifes customers is a T/A Firebird nut like me and he asked me if I am getting gas at the same station all the time. I told him yes, I use Chevron. He said go somewhere else so I went to Mobil. No more stalling. It even has more pep than it ever did. It is now very responsive. Now it did stall just once after I refueled, but only once. I put in half a tank so I will see what happens the next time I refuel. I will keep you posted. Do you think thats really all it could have been? As for the trans. fluid, no it is not orange it is pink leaning towards red. I have had automatics my whole life and the fluid looks perfect. I hoping the crappy gas at Chevron is all that it is :)

Well it could be. I have seen gas cause many problems if it is bad. Never thought Chevron would be one of them. I use Chevron in my baby 98 Mustang so maybe I should change to Shell to see if it runs any different. I am not have any problems but if there gas isn't top notch then it time to make a change. I should have asked if you tried a different gas station sorry. I would also like to recommend putting a can of seafoam into the gas next fill it is an great cleaner. If you been getting bad gas it will help with cleaning things up. Let me know how it goes.

Will do. I did use the STP fuel injector clearner, but will put a can of seafoam in on next fill up. I put more gas in today and it stalled only once. I restarted it and it stayed idleing, no bogging. I also drained the radiator fluid and pit in Prestone Super Radiator Cleaner. says to run for 3-6 hours, then drain and fill with 50/50. Gonna do as it says. I really thinks it was the gas. She is running a little better today than is was yesterday. Will keep ya updated afer I use the seafoam. Thank you for you help so far. I really do appreciate it. :)

Cool that will work.