FJO Air Fuel problem?
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Joined: Feb 2002
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From: Rochester
FJO Air Fuel problem?
I just installed and tuned my AEM EMS in my car. I have the UR first version turbo kit installed. I also installed a FJO 02sensor and FJO A/F monitor. After the tune the monitor read 13.5ish on cruise little throttle (NORMAL), 13.5~14.4 on WOT (LEAN) but it jumps to 10.5~12.1 just around when the throttle is off WOT, and the BOV goes off. Also when I'm cruising and I have the throttle completely off and the speed is dropping than it reads 20.00 
(BYE BYE MOTOR). Weird thing is that I had a ticking issue that was resolved that it came from a heat shield above the turbo manifold. The ticking noise originally was around 3~4000 RPM but now itz in every RPM and itz louder than before. I fear my motor might be blowing....?? help help
Tuner
(BYE BYE MOTOR). Weird thing is that I had a ticking issue that was resolved that it came from a heat shield above the turbo manifold. The ticking noise originally was around 3~4000 RPM but now itz in every RPM and itz louder than before. I fear my motor might be blowing....?? help helpTuner
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From: Sydney
The lean reading off throttle is completely normal. You're backing off so the injectors aren't pumping fuel and combustion isn't occuring. So the resultant 'exhaust' is just air pumped through. It's very high in oxygen but it isn't hot because it hasn't burnt.
As for the rich reading I guess you are referring to the transition between WOT and closed throttle. There is a period right after the throttle has closed when there is still pleny of fuel in the ports and combustion occuring but no air getting through. Hence the rich reading.
Don't be too concerned about transient readings. These conditions are perfectly normal and nothing to be concerned about.
As for the rich reading I guess you are referring to the transition between WOT and closed throttle. There is a period right after the throttle has closed when there is still pleny of fuel in the ports and combustion occuring but no air getting through. Hence the rich reading.
Don't be too concerned about transient readings. These conditions are perfectly normal and nothing to be concerned about.
Joined: Jun 2002
Posts: 1,497
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From: Stockton Heath, Cheshire
Tuner, everything you listed was happening to me about a month ago, the AFR figures are the same 'nothing to worry about other than being abit lean around the 13.5-14.5 mark.
The rattle I had sounded like a tinny rattle which I'm sure wasn't pinking or dettonation
anyway we changed the plugs and fiddled with the MAP on my AEM and the rattle stopped so it could have been dettonation but I'm not convinced or it could have been bad plugs!?!
Have someone look at it straight away though!! as it didn't sound healthy when mine was doing it so I didn't drive it "at all".
Hope this helps
Andy
The rattle I had sounded like a tinny rattle which I'm sure wasn't pinking or dettonation
anyway we changed the plugs and fiddled with the MAP on my AEM and the rattle stopped so it could have been dettonation but I'm not convinced or it could have been bad plugs!?!Have someone look at it straight away though!! as it didn't sound healthy when mine was doing it so I didn't drive it "at all".
Hope this helps
Andy
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