Car is Spuddering

[00Beast]

Each car is different. Post up what you see: key on engine off and key on engine idling.

[bonnieandclyde]

it seems like renting the gauge is the same price as just buying one.

[bonnieandclyde]

i wonder if i should buy a new maf sensor?

[01bonneSC]

Have you tried cleaning it?

[bonnieandclyde]

yes i already tried cleaning it.

[bonnieandclyde]

update...
when im driving it, it spudders so much that it shakes the whole car and doesnt want to go.. at idle at a stop light it revs up and revs down. it also cuts off sometimes when im at a stop light.

[bonnieandclyde]

well the dtc code p0171 came on again this morning. and it was running rough. then i cleared the code and it drove good no hesitation the whole 2 hour commute. so i definately think its just a bad maf sensor. so i ordered the maf on ebay. also i ordered the fuel pump while i was at it. i figured it was 10 years old, i might as well change it out as well. i picked it up for 65 dollars. and the sensor was 60. i was going to change the pump out this weekend. i am a beginner to intermediate mechanic. i was wondering if you guys could let me know if there is anything i should look at or be careful while i change the pump?

[bonnieandclyde]

changed the maf and still the P0171 code comes on. what next to change out?

[01bonneSC]

I can't remember, did you do the O2?

[bonnieandclyde]

no, not yet.

[01bonneSC]

How many miles? Does it look like a factory unit?

[bonnieandclyde]

car has 125000. and the exhaust o2 looks factory.

[01bonneSC]

Wouldn't hurt.

[bonnieandclyde]

does anyone have a picture of all the sensors on my car. and what the volt meter reading should be on all of them. i want to put a multi meter reader on them to test them. also is there a way to test the coil packs?
thanks

[myfirstbonnie]

Your friendly techinfo section for the coils:

http://www.pontiacbonnevilleclub.com/fo ... =48&t=1683

What sensors are you wanting to test with a meter?

[bonnieandclyde]

all the sensors that i can test LOL

[myfirstbonnie]

Good place to start............................techinfo at the top of every page.

http://www.pontiacbonnevilleclub.com/fo ... m.php?f=48

[bonnieandclyde]

does anyone know what volts both o2 sensors should read? i have the scan tool to read that data.

[00Beast]

They should be cycling very quickly between about 800 and 30 or so. The cycling rate is more important than either number. If they're cycling slower than once a second, they're likely bad. The reading is in OHMs, IIRC.

[Archon]

These descriptors may help you.

The PCM supplies a bias voltage of about 450 mV between the HO2S signal and low circuits. When measured with a 10 megohm digital voltmeter, this may display as low as 320 mV . The oxygen sensor varies the voltage within a range of about 1000 mV when the exhaust is rich, down through about 10 mV when exhaust is lean. The PCM constantly monitors the HO2S signal during closed loop operation and compensates for a rich or lean condition by decreasing or increasing injector pulse width as necessary.

The PCM continuously monitors the Heated Oxygen Sensor (HO2S) activity for 120 seconds . During the monitoring period the PCM counts the number of times that the a rich to lean and lean to rich response is indicated and adds the amount of time it took to complete all transitions. With this information, an average time for each transition can be determined If the average response time is too slow, a DTC P0133 will be set. A lean to rich transition is indicated when the HO2S voltage changes from less than 300 mV to greater than 600 mV . A rich to lean transition is indicated when the HO2S voltage changes from more than 600 mV to less than 300 mV . An HO2S that responds too slowly is likely to be malfunctioning and should be replaced.