Mileage drop after cleaning Injectors

Discussion in 'General Maintenance' started by Naveen, Jul 12, 2011.

  1. Naveen

    Naveen New Member

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    I have a five year old Maruti Alto (MPFI). I get the fuel Injectors cleaned once every year.
    Everytime the injectors are cleaned the mileage drops drastically and takes about 1-2 months to get back to normal.

    Why does that happen and how could it be prevented ?
     
  2. Codename.47

    Codename.47 Guest

    does it?
    I never noticed that I just use injector cleaner liquid.
    May be injector is not working at full potential when not CLEANED and then it gives you more mileage and of course engine is running under its normal power.
    When you clean it , it tends to become better at performance giving you less mileage.? just a thought
     
  3. gagan_singh

    gagan_singh Super Moderator

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    i agree with rahul. the injector is probably just not spraying as much as it is suppose to because its dirty. so u save some fuel but lose some performance. i would rather get that little bit of extra performance cause it would be better for ur engine to, it will run at what it was tuned to run at!!
     
  4. Codename.47

    Codename.47 Guest

    yeah thats what i thought. lets see what dhhawal has to say
     
  5. Dhhawal

    Dhhawal New Member

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    you guys r right on the money, but i think this case could be a little more complex, the metering of the fuel is controlled by the ecu and since the load of the car is the same in both the case, if the injectors are clogged, the car should feel underpowered and give a worse mileage figure because the engine will have to work harder to lift the same load...however before we get into any specifics, @naveen, from where do you get your injectors cleaned? and second of all, what the change in the mileage like; before and after?
     
  6. Codename.47

    Codename.47 Guest

    dhhawal bhai .. too technical :p
     
  7. Dhillon

    Dhillon Administrator Staff Member

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    I have also notice this,(Zen mpfi) got the injectors cleaned at Maruti Service Station and there was a noticeable drop in average for couple of tank fulls.
    There was none to nill improvement in engine performance.
     
  8. Dhhawal

    Dhhawal New Member

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    hmm, now i think thats a problem related to the ecu, i think before cleaning the injectors they probably disconnected the ecu, and its taking time to adjust to the new fuel flow rates, the only way to know for sure is getting your exhaust gases checked to see the amount of unburnt HC percentage in your exhaust..!
     
  9. Codename.47

    Codename.47 Guest

    that is a good point but doesnt disconnecting the ECU put the car in Reset mode. Mean all the defaults
     
  10. Dhillon

    Dhillon Administrator Staff Member

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    Should the ECU take that long to adjust ? I always thought it dynamically adjusts to the quality and octane rating of fuel.
     
  11. Codename.47

    Codename.47 Guest

    Well it wouldnt really read the Octane value I am pretty sure.
    If you have just started the car and its pretty cold out there. the car will run rich means the ECU will send more petrol in the inlet
     
  12. Dhhawal

    Dhhawal New Member

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    i guess it depends on the kind of ecu that you have in your car, racing cars may have chips that can adapt very quickly to changes in sensor readings, perhaps for economy sake, they may use ecu that are cheaper but are slower to respond to changes in the sensor inputs, can't say for sure, but this is one theory..!
     
  13. gagan_singh

    gagan_singh Super Moderator

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    he can get a wideband for his air/ fuel ratio. i got one from aem for about $210 and installed it my self. it helps alot, because of it i narrowed down my exhuast leak. knew it was before the wideband thats why it was reading a very lean rating.
     
  14. Dhhawal

    Dhhawal New Member

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    thats a helpful suggestion, he can find out if his afr is running rich
     
  15. Naveen

    Naveen New Member

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    thanks for all the advice.
     
  16. Codename.47

    Codename.47 Guest

    did you get it check again mr naveen
     

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