please help me!!!
bbaca
05-28-2011, 11:17 PM
i have a 2000 pontiac grand prix gtp and every time i start it, it will start puttering but it will drive a lil wile then it will die after bout 5 min at the most its blowing black smoke out the tail pipes and its smoking under the hood does any body have any suggestions about what it could be
GTP Dad
05-29-2011, 10:47 AM
Welcome to AF!!
The first place to start is with the catalytic convertor. It may be blocking up and causing the car to stall. The rich condition you currently have has damaged it and that would cause the car to stall. However, the rich condition will need to be corrected before you do anything else.
You obviously have a rich condition given the fact that the you are blowing black smoke out the tail pipe. You may have a stuck injector, bad plugs, dirty air filter that is restricting air flow, a dirty Idle air control motor, bad Mass Airflow Sensor (MAF) and a host of other issues.
I would start by pulling the plugs to see what they look like. If you find wet plugs or plugs that are covered with carbon that indicates incomplete combustion and I would start looking for an issue with the fuel delivery system. Changing plugs alone may help the issue. Once the plugs are changed check the fuel pressure to make sure it is good. This should be done with the key off and with the key on. This way you can find out whether the injectors are holding pressure.
Since the car is stalling as you indicated there are a couple of possible causes. First unplug the MAF sensor and see if the car stalls out, it may even run better if the sensor is bad. If there is no change you may have an issue with the crank position sensor being bad and causing a stalling issue.
One thing you didn't say is whether you have a check engine light. If you do have the car scanned to see if there are any codes. This will give you some indication of where the problem may be.
I hope this helps as it is hard to tell you everything to check in a forum post. If this doesn't help you find the problem post again and we can try some other things.
The first place to start is with the catalytic convertor. It may be blocking up and causing the car to stall. The rich condition you currently have has damaged it and that would cause the car to stall. However, the rich condition will need to be corrected before you do anything else.
You obviously have a rich condition given the fact that the you are blowing black smoke out the tail pipe. You may have a stuck injector, bad plugs, dirty air filter that is restricting air flow, a dirty Idle air control motor, bad Mass Airflow Sensor (MAF) and a host of other issues.
I would start by pulling the plugs to see what they look like. If you find wet plugs or plugs that are covered with carbon that indicates incomplete combustion and I would start looking for an issue with the fuel delivery system. Changing plugs alone may help the issue. Once the plugs are changed check the fuel pressure to make sure it is good. This should be done with the key off and with the key on. This way you can find out whether the injectors are holding pressure.
Since the car is stalling as you indicated there are a couple of possible causes. First unplug the MAF sensor and see if the car stalls out, it may even run better if the sensor is bad. If there is no change you may have an issue with the crank position sensor being bad and causing a stalling issue.
One thing you didn't say is whether you have a check engine light. If you do have the car scanned to see if there are any codes. This will give you some indication of where the problem may be.
I hope this helps as it is hard to tell you everything to check in a forum post. If this doesn't help you find the problem post again and we can try some other things.
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