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1999 GMC Suburban 1500 Question: engine turn over but won't start

 

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rx7, 5.7L V8, Norfolk, VA, January 16, 2010, 20:26
 Rookie

I started the suburban this morning and the engine hesitate and misfire. After I shut it down and it won't fire back up. Take off all the plugs and they all foul. Change them and it still won't fire up. Check the cap and rotor, they're all fine. I gave it a full tune up with all new plugs, wires, cap and rotor, filters before the winter. Put the scanner on shows no code. Check the distributor drive gear by turn the rotor, it's has no excess free play. Check the Crank Angle Sensor, it has 12V and ground and 5V by crank the engine. Same as the Cam Angle Sensor. Will the O2 sensor and the EGR valve causing the problem? Please help.

It has spark on all cylinder but fuel were on the plugs. Engine compression are good in all cylinder. It seems the spark timing is in-operate with the fuel. So, I think maybe the problem from the distributor gear, crank angle sensor or the cam angle sensor. But I find nothing wrong with them.

One thing I may expected is would I use a cut-off key to activate the engine disable from the security system? If so, how do I dis-arm it?

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  • Answer #1

    Bret Bodas from RepairPal Test Shop, January 17, 2010, 17:10
     Master

    The O2 sensor and EGR Valve won't cause this. Are you seeing fuel on the plugs when you remove them? Have you checked for spark at the plugs? How about fuel pressure?

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