hesitate and backfires when hot

1997 MERCEDES BENZ C280
101,000 MILES • 6 CYL • 2WD • AUTOMATIC
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OELSMIL
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  • 1 POST
My 1997 Mercedes C280, when the engine just started it runs good, and idling good. when the engine gets hot(not overheating) it hesitate and backfires, but the idle is always good. It can only run 5-10 mi/hr.The fuel pressure is right on the specs. The Check Engine light is not on and there is no pending code. What could it be the problem.
Feb 24, 2011 at 2:08 AM
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JACOBANDNICKOLAS
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Have you checked for vacuum leaks? Have you checked the intake to make sure there are no leaks there? Also, have you tried driving the vehicle while a scanner is plugged into it to check for live data that would lead you to the problem. Also, I am assuming the fuel pressure is good while this is happening. If that is wrong, let me know. Final questions, does it backfire through the exhaust or the intake? Is there any smoke related to the backfire or fuel smell? And, have you checked the EGR?
Feb 25, 2011 at 2:15 AM
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FIXITMR
  • CAR REPAIR CONTRIBUTOR
  • 9,990 POSTS
these cars are known for MAF sensor and WIRING harness issues.
Feb 25, 2011 at 2:55 AM