1995 OLDSMOBILE 98
139,500 MILES
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Car starts and runs fine. driving down the highway at 70 mph and will stall out. was starting right back up but now isn't until i pull the wiring coupler off of the mass air flow sensor. Replaced yhe MAF sensor with no results. am assuming it is a sensor of some sort since it will still run with MAF disconnected. Any ideas?? Thanks!
Apr 1, 2013 at 12:07 PM
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JACOBANDNICKOLAS
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Have you checked the map sensor? Have you checked the fuel pump pressure?
Apr 1, 2013 at 12:09 PM
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No i can hear the pump kick on and since it will run for about 20 miles before stalling and will run after i take the wires off the MAF that fuel pump is not the issue?? Also cannot check codes as this vehicle Is obd 1 but has an Obd 2 connector. I did pull the idle air control and have cleaned it. Pulled the air intake and cleaned the honeycomb screen on the throttle body..
Apr 1, 2013 at 12:21 PM
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Also have replaced some of the vaccum lines that i found were bad.
Apr 1, 2013 at 12:25 PM
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JACOBANDNICKOLAS
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I have seen issues like this that were caused by a bad map sensor and a lazy fuel pump. The pump may not be keeping up with the demand at higher speeds.
Apr 1, 2013 at 12:31 PM
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OK thanks will do some checking on these. is there any test to check the MAP??
Apr 1, 2013 at 12:41 PM
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I always do an active test... while driving, my scanner provides real time information. I can watch how it reacts.
Apr 1, 2013 at 12:45 PM
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Also car will start and run fine again after sitting over night. reconnect the MAF but will also die while just driving around town at 35-40 mph. seems something is heating up and then not operating properly?? will take it in for a fuel pressure check.
Apr 1, 2013 at 12:51 PM
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JACOBANDNICKOLAS
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You can test fuel pressure yourself. It's easy. There is a how to video and directions on our homepage under the DIY section.
Apr 1, 2013 at 2:19 PM
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Fuel pressure at the rail is 45-46 kbs which i believe is within specs. have changed plugs and wires with no change. TPS and idle air control valve are new also.
Apr 18, 2013 at 3:46 AM