K1500 lacks power

Discussion in 'Chevy Truck Forum' started by cdma1030, Jun 30, 2013.

  1. cdma1030

    cdma1030 Full Member

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    I have a 94 k1500. During acceleration it seem to lack the power that it should have. You can feel that it is sluggish then sometimes it will come into to it and take off more like it should. It is very erratic. I have checked fuel pressure and it held steady at 15lbs. I have changed fuel filter, plugs, wires, coil, and tps. Could it be the fuel pressure regulator? Im at a loss. When I pull my boat you can really notice loss of power. Starts and idles good. Any help would be greatly appreciated.
     
  2. 96silverado

    96silverado Full Member

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    If this were my situation,i'd befound in the garage cleaning the EGR,then the IAC
    simply for good measure and elimination processes..
     
  3. cdma1030

    cdma1030 Full Member

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    I unplugged egr and connected it to a direct vacuum hose and motor stumbled. The IAC I replaced about 2 years ago. I have also replaced cap and rotor.
     
  4. Boudin

    Boudin Forum Moderator

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    This model uses the MAP sensor (manifold absolute pressure), TPS (throttle position sensor), and engine RPM to tune the engine for the best power and efficiency. Later models used the MAF (mass air flow) sensor and problems like you are describing sometimes were solved by cleaning it. I don't know of any kind of maint to be done on these three parts that your ECM uses to fine tune the motor. Anyone?

    I don't see why you would think regulator if you are reading 15 psi. That is on the upper end of the range (9-15 for TBI).

    I'm not sure what to tell you. Do you have a check engine light at all? What about O2 sensors or a clogged catalytic converter?
     
  5. cdma1030

    cdma1030 Full Member

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    The fuel pressure guage was connected right after the fuel filter. No light on and no catalytic converter.
     
  6. chevychase

    chevychase Senior Moderator Staff Member

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    Take a look at the injectors flow pattern.. both should be a nice fan/coned shaped pattern..with no droplets of fuel.
    This could be a lean..or rich condition. Does it sputter..or backfire any? Look at the pattern let us know.
     
  7. Boudin

    Boudin Forum Moderator

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    Thats good. I still don't know what about it makes you think regulator. I would be happy to have 15 psi. No cat? Well that eliminates that as a potential problem. An o2 sensor going bad will usually give you a CEL.

    Have any of the things you have done improved it at all? Good idea on checking the pattern. I would certainly do that as well.
     
  8. cdma1030

    cdma1030 Full Member

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    Not as good as was on my phone.
     
    Last edited by a moderator: Mar 17, 2016
  9. chevychase

    chevychase Senior Moderator Staff Member

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    Video not to clear? looks like maybe pattern is a little rich? But seeing you have no check light...will cost 11 bucks to get this out of the equation.
    This sensor can cause all kinds of trouble/symptoms..coolant temp sensor.
    Will be at thermostat housing ..2 wire sensor.
    [​IMG]
     
  10. chevychase

    chevychase Senior Moderator Staff Member

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    Trust me change it ..will not hurt also can cause this but no check light. this is the most important injection sensor ..all relies on it..even newer vehicle.
    The ecm..watches this sensor at all times ..uses it to control fuel timing air ect.
     

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