car wont start...im stumped......
07-07-2010, 03:24 PM
#1
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car wont start...im stumped...... this past weekend my 1998 Z28 started acting funny. it dropped rpms, spuddering, stalled out in traffic a few times, and had a code pop up.
code was P0108 MAP/BARO circuit high. so i got a new sensor, replaced it, and now the car wont start. it has spark, fuel, all the lights and radio come on, no fuses are blown, the battery is less than a year old, same with the starter.
anyone have any ideas?
code was P0108 MAP/BARO circuit high. so i got a new sensor, replaced it, and now the car wont start. it has spark, fuel, all the lights and radio come on, no fuses are blown, the battery is less than a year old, same with the starter.
anyone have any ideas?
07-08-2010, 06:59 AM
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i replaced the MAP sensor not the MAF sensor. you know the one thats on the back of the manifold
07-08-2010, 10:11 AM
#6
My bad, I was sidetracked and assumed MAF because you always see those threads, not really many related to the MAP sensor. Anyways, you can still have an issue with a bad vacuum leak although I'm not sure if that would prevent the car from actually starting.
You should also be able to measure the voltage at the sensor. It is in 5 volt reference to see if you are getting communication from the PCM. It could even be a PCM problem where you might need to get the pin out for the map sensor and see if anything is coming from the PCM. Or it could be cut wires if you are getting power from the PCM but not at the sensor.
Did you replace the MAP sensor with an aftermarket sensor or GM? With it not starting at all I'm thinking you don't have power to the MAP sensor....especially since you replaced it and nothing changed. Check the power at the MAP first.
You should also be able to measure the voltage at the sensor. It is in 5 volt reference to see if you are getting communication from the PCM. It could even be a PCM problem where you might need to get the pin out for the map sensor and see if anything is coming from the PCM. Or it could be cut wires if you are getting power from the PCM but not at the sensor.
Did you replace the MAP sensor with an aftermarket sensor or GM? With it not starting at all I'm thinking you don't have power to the MAP sensor....especially since you replaced it and nothing changed. Check the power at the MAP first.
07-08-2010, 02:34 PM
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the car ran great the night before. and i had it idling for about 5 minutes putting in some camping gear for the weekend. 3 blocks away from the house is when it started
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07-08-2010, 08:40 PM
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07-09-2010, 08:00 AM
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For the heck of it, put the old MAP back in. Maybe, just maybe the new one is junk. Then, how much have you been cranking on this thing to try and start, have you pulled a plug recently? Reason I ask, is I had an alternator issue on a car one time and had been doing some cranking and what not and car ran real rough at end just before battery died etc. Well long story short, plugs got fouled wet with fuel. I took all out, took a propane torch to all of them, put them back in, and car fired right up and all was good. Just a thought and trying to help with cheap easy things to check.
07-09-2010, 03:24 PM
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the car was taken to a garage today. but ill update this when i know
but when i checked for fuel, it almost seemed it was down on pressure. i just brushed it off and thought i was imagining things. a new pump was installed recently.
but when i checked for fuel, it almost seemed it was down on pressure. i just brushed it off and thought i was imagining things. a new pump was installed recently.
