A leak shouldn't effect the dashboard mpg as it's calculated by injector flow rates I believe
So least out the tank and hoses wouldn't show up
General 1.2 consuming too much fuel
- Thread starter Chali
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General 1.2 consuming too much fuel
A leak shouldn't effect the dashboard mpg as it's calculated by injector flow rates I believe
So least out the tank and hoses wouldn't show up
Today i took my car for 20 miles run on motorway and surprisingly it gave me 54mpg on motorway (60mph), but as soon i went to city roads it again went to same 27-30 mpg ?
Can bad coils or leads effect this , as engine runs on less rpm in city, may be less current is passed from coils or it is same always ?
Can bad coils or leads effect this , as engine runs on less rpm in city, may be less current is passed from coils or it is same always ?
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it measures fuel in the tank, ABS wheel sensors and the ECU injector timings and then calculates
generally its fairly accurate over long time. However its way off after you keep pressing the reset button or the battery has been disconnected.
It best over hundreds of miles or better still thousands of miles
That’s not how coils work.
That said it’s funny how you get normal consumption on a good run. Where as the economy goes down when you’re in city traffic. I would like to refer you to my previous point about high fuel use of you’re sat waiting in traffic and burning fuel while not moving or moving very slowly.
Also how are you measuring your fuel use are you watching the instantaneous consumption ?
Avg consumption
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Hi All
Sadly still no photo of the cam positioning.
Tim
Sadly still no photo of the cam positioning.
Tim
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Fuel figures from the trip computer are not reliable. Zero the miles trip, Brim the tank, then when you brim it again you will know exactly ho many miles you have done and the type of driving.
wasn't this said on the first set of posts regarding this car, certainly going around in circles (maybe why its using to much fuel :bang
As to get over with the excessive fuel consumption, i replaced number of things, o2 sensor, spark plug, thermostat, and lastly i changed coilpacks (delphi) and spark plug wires( NGK )
Car is running same as before, but on idle if AC is turned on, engine stalls !
Is there any thing to do with obd or ecu ???
Car is running same as before, but on idle if AC is turned on, engine stalls !
Is there any thing to do with obd or ecu ???
Should run fine with the MAP disconnected. Might need the battery disconnecting if its learnt some way out values
We keep going round in circles. Before moving onto other things we need answers to questions asked a long time ago.
Also the Crank was one tooth out. Strange it still preforms the same now its been corrected
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strange mine runs fine 1.2 05 and cable operated throttle. Defaults to a slightly rich default
maybe someone with a flyby wire throttle body could try.
ecu measures various sensors and determine what the idle should be.
usually calculates a value of between 850 - 1200 RPM
reading from the Crank sensor it alters what it expects to see to what its actually reads via the idle control valve built into the underside of the throttle body
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The engine ECU sends the signal to the aircon compressor clutch to turn on and off the aircon there isn’t a switch to tell the ECU the ECU controls the switch.
The switch on the dash tells the computers you want the aircon on and the ECU will look at the pressure sensor in the air con system to see if it will allow the aircon to switch on.
Now all that said, on modern cars the car should not increase the idle when you switch on the aircon it could manage engine power/mixture to make sure the idle remains the same when the aircon is in use.
That’s still not your problem though.
The switch on the dash tells the computers you want the aircon on and the ECU will look at the pressure sensor in the air con system to see if it will allow the aircon to switch on.
Now all that said, on modern cars the car should not increase the idle when you switch on the aircon it could manage engine power/mixture to make sure the idle remains the same when the aircon is in use.
That’s still not your problem though.
But Why ECU is not Telling the throttle body to increase rpm on idle when AC is on, it might be telling but the switch on throttle body is not working ??
Poor battery will also cause poor idle control.
there's no easy way to tell if the throttle body is working correctly. Substation is the easiest way.
Something like MES shows expected RPM against actual RPM which should be around the same values. If the ICV isnt working correctly the values will be different.
you can try cleaning it with throttle/brake cleaner. You have to take the body off on mine there is a plastic cover over the ICV that can be pushed out of the way
