car runs at idle when goes over 35mph dies

1990 PONTIAC GRAND PRIX
200,000 MILES
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ROYZ11
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replaced fuel pump and filter ck fuel pressure gd has spark constent
Sep 16, 2011 at 12:02 AM
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SATURNTECH9
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Have you checked for codes?Have you checked your exhaust back pressure?
Sep 16, 2011 at 12:33 AM
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ROYZ11
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how do you ck back pressure
Sep 16, 2011 at 1:04 AM
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SATURNTECH9
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You would remove the o2 sensor install the back pressure tester adapter where the o2 sensor goes.Then hook up the gauge start the car hold the rpms up to about 2,000 rpms for 30 seconds and see what the readings are.Or take it to a exhaust shop and have them test it.Have you checked for codes?
Sep 16, 2011 at 1:27 AM
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ROYZ11
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map sensor came up 33 44 45
Sep 16, 2011 at 1:37 AM
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SATURNTECH9
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I need to know what size engine you have and if its thr 3.1L if its turbo or not?Also do you have a scan too that can read live engine data on your car?
Sep 17, 2011 at 12:05 AM
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