Eng misfiring while driving and very bad at idle

Tiny
JOSHUARMILLER
  • MEMBER
  • 2003 MAZDA MPV
  • 138,000 MILES
Van idles very bad fixed numerous vaccum leaks cleaned mass air flow sensor fuel pressure at 70 psi. There are no codes except for a post cat code on bank 2 for heater circuit. Can't get scanner to give me mode six data. Tried unplugging coils to look for a "no change condition". Looking for a place to start testing but don't know where to start any ideas
Sunday, August 25th, 2013 AT 1:12 PM

6 Replies

Tiny
KHLOW2008
  • MECHANIC
  • 41,814 POSTS
Were the spark plugs checked?
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Monday, August 26th, 2013 AT 11:07 AM
Tiny
JOSHUARMILLER
  • MEMBER
  • 4 POSTS
They were replaced with the fuel injectors
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Monday, August 26th, 2013 AT 11:29 AM
Tiny
JOSHUARMILLER
  • MEMBER
  • 4 POSTS
Plugs are soaked in fuel
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Monday, August 26th, 2013 AT 11:31 AM
Tiny
KHLOW2008
  • MECHANIC
  • 41,814 POSTS
Plugs are soaled in fuel indicates excessive fuel is getting to the cylinders and it could be a fault with the pressure regulator or engine coolant temperature sensor.

Use the casn tool to monitor the ECT to see if it is working correctly.
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Monday, August 26th, 2013 AT 11:37 AM
Tiny
JOSHUARMILLER
  • MEMBER
  • 4 POSTS
Will do thanks
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Monday, August 26th, 2013 AT 11:39 AM
Tiny
KHLOW2008
  • MECHANIC
  • 41,814 POSTS
Any update on this?
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Saturday, September 14th, 2013 AT 9:35 PM

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