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I have a 98 youkon 4by4 its been in shop months they

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I have a 98 youkon...
I have a 98 youkon 4by4 its been in shop for two months they called me said it was fixed I left the shop got 3miles down the road its doing the same thing agin when I take off it acts like its smothered out then when I stomp on it it runs fine with a little backfire out the exhaust I've replaced O2 sensors mass air flow sensed spider assembly throttle control sensor wires cap plugs rotar now it's showing the code p0304 cylinder 4 misfire detected what else can be done to fix this problem
Submitted: 3 years ago.Category: GMC
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Answered in 6 hours by:
5/19/2015
GMC Mechanic: Gary, ASE Certified Technician replied 3 years ago
Gary
Gary, ASE Certified Technician
Category: GMC
Satisfied Customers: 18,031
Experience: GCM master tech over 25 years
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Welcome! My name is ***** ***** I will do my best to assist you with this problem.
I am sorry for the long wait
will it back fire out the exhaust or up the intake throttle body ?
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