Question about 1990 Buick Century

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I have tested almost everything

Okay i have had a mech. come out and look at my car. I had 45 psi in my fuel line, had volts running to my injectors. also had a spark tester and found good spark. the cam sensor was checked as well the only thing that he or i could figure was the air intake sensor.....my question is could a knock sensor or a crank position sensor cause it to not start or when i can start cause it to bog out when given gas. the only other thing is a exhaust clog but it seemed fine before all of the this dosen't an exhaust clog build over time thank you for your help me and my family are broke down now for 3 days on the road and are still 5 hours from home so any advise is helpful.

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  • robertmizell
    robertmizell Jan 29, 2014

    injectors should read 12 ohms on volt meter one or more is probably bad

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If you have spark, the crank sensor is working. A bad knock sensor won't prevent the car from starting. It sounds like you don't have fuel going into the engine. The injectors will always have 12v to one side when the key is on. The computer switches the ground side to open and close the injectors. This happens ten times a second. If you have access to a test light, you can hook it up to the two wires from one of the injectors and crank the engine. The test light should blink on and off. If not, then something is not telling the ECM to work the injectors. The most likely cause is the ignition module in the distributor (or under the coil pack if you have Direct Ignition System). I serves two purposes. On is to trigger the ignition an create spark, the other is to trigger the ECM to work the injectors. That part of the module may have gone bad. As for the clooged exhaust, the car would still start for at least a few seconds. I don't think that is your problem.

Posted on May 03, 2010

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I have a century with the same problem. its the 3.3L and ran great on the interstate till it quit. i have checked everything and am using my girlfriends 90 century that runs great as doner parts. the best that i can find is that with a noid light i have no injector pulse at all. have installed a new crank sensor, no start. i swaped computers, no start. it will run all day as long as i feed it gas through a vac port in the intake. now im going to check for a loose pin on a connector. im lost on this!!!!!

Posted on Jul 11, 2010

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Yes a plugged exhaust would allow you to start and as you drive it would loose power,has the tech scanned computer for codes, and also is the egr stuck open with carbon,if you have spark and good fuel preasure then the crank sensor is not the problem,you may have a bad mass air flow sensor or a bad computer,if the intake temp sensor was bad the car would still run,one more thing to check is the coolant temp sensor and the throttle postion sensor, i know this is alot to check but this is where i would go with my check, good luck, let me know what happens,

Posted on May 03, 2010

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