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Old 01-02-2011, 05:19 PM
Rahulio1989300E's Avatar
Rahulio1989300E Rahulio1989300E is offline
V10s & V8s FTW!
 
Join Date: Jan 2005
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Quote:
Originally Posted by duxthe1 View Post
I think you are confusing the lambda signal with the O2 signal. When lambda is over 50% the engine is running lean and the ecu is enrichening the mixture. Reading under 50% the engine is running rich and the ECU is pulling fuel out. Reading ~90% lambda indicates the engine is very lean either due to the adjustment being way out or possibly a vacuum leak inadvertantly caused during the previous repairs. After ruling out vacuum leaks you'll be fine to enrichen it to approx 45-55% lambda.
So what you are saying is that my understanding of the duty cycle reading is wrong?

What I did think:
A duty cycle reading of near 100% indicates overly rich conditions.
A duty cycle reading of near 0% indicates overly lean conditions.

What I need to think:
A duty cycle reading of near 0% indicates overly rich conditions.
A duty cycle reading of near 100% indicates overly lean conditions.
AND
Duty Cycle = Lambda?



I am fairly certain that all possible vacuum leaks are taken care of. In the last 3 months I have replaced every single rubber elbow and connector from the firewall to the radiator, and the one that connects to the transmission. Both ICV hoses have been done, and now the intake boot and fuel injector seals. I guess the only possible leak is from the mixture tower itself since the small factory ball has been removed. I JB welded the rough port where someone had drilled into the side of the mixture tower to remove the taper-proofing ball. I can't imagine there being a vacuum leak somewhere but I will have to double check everything, including the seating of the new rubber intake boot to the throttle body.
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