2000 Grand AM - Please Help!

Hello guys!

I have a 2000 Pontiac Grand AM and yesterday when I drove it it was real lazy. I pushed the gas til the end and it just didnt make any sense. The car was totaly dead and then it turned off alone. This has been happening for some time now and when ever it is hot outside and I drive the car, it becomes lazy after couple of minutes. Also, when I push the gas more, the car starts to shake and RPM continues to go down as the car too. I would appriciate any help I can get.

P.S. I had the motor changed last year and the light "Service engine soon" is always on and I checked it with the computer from Checker and it says some kind of a "air pump".

Thank you.

What engine?

Sounds like probably low fuel pressure, drive with a guage hooked up and see if the pressure drops when it acts up. Could also be MAF or TPS, while you're at it, check the reading of all the sensors.

Didnt you have a probelm with the air pump before ?
http://www.automotiveforums.com/vbulletin/showthread.php?t=771867

Youre going to have to get a better scan IMO other wise your guessing, but as J-Ri said sounds fuel related, could be your fuel pressure regulator or your fuel pump.

What engine?

Sounds like probably low fuel pressure, drive with a guage hooked up and see if the pressure drops when it acts up. Could also be MAF or TPS, while you're at it, check the reading of all the sensors.

Than you for replying.
I have 3.4 liter motor. I also forgot to mention that the scale for the fuel sometimes works and sometimes it dont. Like when I turn the car on the scale drops to an "Empty". I'm sorry, but I dont understand what do you mean with "MAF or TPS". I did post here before about air pump but I wasnt sure. I have that problem aslo. Thank you for the help.

Didnt you have a probelm with the air pump before ?
http://www.automotiveforums.com/vbulletin/showthread.php?t=771867

Youre going to have to get a better scan IMO other wise your guessing, but as J-Ri said sounds fuel related, could be your fuel pressure regulator or your fuel pump.

Thank you.
I will look for more info on the internet. I hope you guys can help me too.
Thank you again.

I went to the Pontiac service and they said I need these things:

CATALYIC CONVERTER
OXYGEN SENSOR
FUEL LEVEL SENSOR AND FUEL PUMP


Total would be $1700 with labor and everything.

I went to the Pontiac service and they said I need these things:

CATALYIC CONVERTER
OXYGEN SENSOR
FUEL LEVEL SENSOR AND FUEL PUMP


Total would be $1700 with labor and everything.


If it were me I'd at least shop around to other mechanics. If you're able to do the work yourself, start with the fuel pressure regulator, you'll have to locate the vacuum hose going in to the corner of the upper intake manifold, run the engine and see if your getting a constant sucking feeling, the fp regulator is a small vac canister that feeds the injectors, it's a fairly common problem with your motor. The other thing I'd do is go back to whom ever replaced your motor and have them fix it, they can at least tell you how if they won't do it.

Yeah coden that level float is a problem with the 99-02 models, the tank does have to be removed to replace this.

I wouldnt think your fuel pump is bad already, I have a 99 w/180k miles and its still pumpin along. :dunno:
You can check your fuel pressure(41-47 PSI) and this would giv you an idea what its running at, but your fuel pressure regulator is much cheaper and very easy to replace.

If you are close to, or over, 100k miles your O2 sensors need replaced anyways. Then you can hav your cat tested again to see if it's still reading high .
A muffler shop will be pretty cheap on thier Cat. Convert.s.

My Beretta has 159,000 miles on it and my Grand Am has 190,000 miles. Both are the original fuel pump as far as I know. They will last a long time if you keep more than 1/4 tank in them all the time. I know theses are the module kind that are always submerged in fuel, but it seems to make a difference even in these.

Do the cat first! Sounds like it may be blocked. This will give you false readings on the O2 sensors and definitely give you a huge performance problem driving. There is a factory warranty on most cats but I think its only ten yrs (check this with your dealer) The gauge problem isn't likely related but just about anyone can change a tank unit but, the part is generally around $200.

If the cat is plugged, it will have performance problems immediately, not after driving for several minutes and it would not change with temperature. The cats also have no effect on performance due to changing O2 sensor readings. Only the upstream sensors are used to determine how much fuel the engine gets, the downstream sensors only tell the computer if the cats fail.

Ok here is the update:

I replaced an oxygen sensor and fuel pump and the car is running with power right now. The guy that replaced my motor last year didnt even put secondary air pump and that's why the "Service Engine Soon" light is on. I will add update once I find an secondary air pump and replace it.

Thank you all.