Sticking injectors when letting off throttle completely
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Joined: Jun 2010
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Sticking injectors when letting off throttle completely
Morning all not entirely sure what section to put this in so figured was best to put it in here.
Evo 5 import
Car is fitted with apexi power fc (no maf)
1000cc rc injectors
2.4 forged engine
Basiclly the problem my car has developed is when i let off the throttle completely 50% of the time my injectors stay at about 2.4% and the AFR goes rich to 10.8 for a second then back off to 11.8 and stays there until throttle is applied. The problem when the cars does this is that it starts to lurch back an forth and judder like it would be if it were misfiring.
The other 50% of the time where the car behaves itself you let off the throttle completely and the injectors turn completely off showing 0% on my apexi power fc hand controller and the AFR reads nothing which is what it should be doing right?? When this happens the car comes down the revs by itself very smoothly with no jurking or anything.
When the injectors are staying open and the car is lurching back an forth the hand controller is not showing any knock of det at all the.
I had problems before with a cam sensor making the car misfire under load and i replaced it with a spare i had at home would another dodgey cam sensor cause this?? or would it more likely be something to do with the throttle body perhaps the ICV playing up?? As to be honest the idle isnt the best either its a bit up and down when the engine is cold but not the bad when upto running temp it sits around 1000rpm
Any help will be appreciated.
Craig
Evo 5 import
Car is fitted with apexi power fc (no maf)
1000cc rc injectors
2.4 forged engine
Basiclly the problem my car has developed is when i let off the throttle completely 50% of the time my injectors stay at about 2.4% and the AFR goes rich to 10.8 for a second then back off to 11.8 and stays there until throttle is applied. The problem when the cars does this is that it starts to lurch back an forth and judder like it would be if it were misfiring.
The other 50% of the time where the car behaves itself you let off the throttle completely and the injectors turn completely off showing 0% on my apexi power fc hand controller and the AFR reads nothing which is what it should be doing right?? When this happens the car comes down the revs by itself very smoothly with no jurking or anything.
When the injectors are staying open and the car is lurching back an forth the hand controller is not showing any knock of det at all the.
I had problems before with a cam sensor making the car misfire under load and i replaced it with a spare i had at home would another dodgey cam sensor cause this?? or would it more likely be something to do with the throttle body perhaps the ICV playing up?? As to be honest the idle isnt the best either its a bit up and down when the engine is cold but not the bad when upto running temp it sits around 1000rpm
Any help will be appreciated.
Craig
my evo 8 does something similar to this, sometimes injectors stay on, and its almost like cruise control... and then it will hit like 3.5k rpm and then you can feel the car decel like it should.