A complete stop the engine shuts off

2003 SAAB 9-3
150,000 MILES • 2.0L • 4 CYL • MANUAL
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WALESKA
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My car keeps shutting off only at a complete stop, but turns back on without a problem. What can be the problem?
Nov 29, 2017 at 11:58 AM
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MHPAUTOS
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Will it hold an idle? Sounds as if the base idle is to low. Also, run a scan for any codes, not all codes will set a check light. Check for vacuum leaks and do a fuel pressure test as well. Start here.
Nov 29, 2017 at 1:17 PM
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WALESKA
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That is the thing it does not always shut off. It can shift off at a stop then I keep driving stop again and it is fine then stop again and the idle goes completely down and it shuts off. I have checked all the hoses and it all looks good. The engine light has been on the code it gave a while back had to do with an oxygen censor.
Nov 29, 2017 at 1:42 PM
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MHPAUTOS
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Can you give me the code? O2 sensors can give bad reading due to vacuum leaks, up stream exhaust leaks, high or low fuel pressure, faulty injectors, and general tune problems. a live data read will show if the O2 sensor is just out of range or has failed completely. this would be worth checking as well.
Nov 29, 2017 at 9:13 PM
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WALESKA
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Code P0491.
Nov 30, 2017 at 4:37 AM
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MHPAUTOS
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Secondary air injection system code.

Potential causes for a P0491 may include: Faulty exhaust manifold check valve A fuse or relay for the secondary air injection pump may be faulty A faulty air pump Leaking vacuum hose A bad vacuum control switch A dislodged a vacuum line A leak in the hoses/piping between the secondary air injection pump and the Combi or secondary air injection A sensor for the secondary air pressure may be faulty The combi valve itself is faulty The secondary air injection port in the cylinder head may be plugged with carbon The secondary air injection ports in the cylinder head may by clogged

Dec 1, 2017 at 8:30 PM