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80kPa on idle?

Posted: Fri Mar 31, 2006 1:26 am
by maztah
ive been tuning my toyota AE101 2E engine and my MAP seems to read a pressure of 80kPA in the manifold on idle running at 900RPM. ive checked the vacuum hose fitted to the manifold and MAP sensor and the hose seems fine same as well as the sensor. Where could be the problem or is 80kPA right? Btw the injection time is 36ms and the pulse occurs everytime my program sees a pulse from the NE pickup signal

Posted: Fri Mar 31, 2006 1:35 am
by sebch
Hi,
IMHO 80 kPa is definitely not correct. Means that you have hardly any vacuum in your inlet manifold. If I were you, I'd check the intake for any air leak between the buterfly and the head: injector bungs, manifold to head gasket, vac line to the brakes, well every hole in the inlet or junction should be air tight. What you can use for that is get your engine idling (if this is possible at all) and then move a fuel soaked paintbrush around the whole inlet system. If there's a leak, it will suck fuel vapors and the RPM will go up when the brush is close to the leak.

Hope this helps, Séb

Posted: Fri Mar 31, 2006 1:49 am
by maztah
thanks sir, i will try that

Posted: Fri Mar 31, 2006 2:52 am
by maztah
another question. during off stage where the engine is not running, what pressure should there be in the manifold?

Posted: Fri Mar 31, 2006 4:33 am
by rs2000
with the car not running the MAP should read around 100 (atmospheric pressure). It will vary place to place..

For your idle proble just double check your timing is correct as this can have a large effect on idle MAP reading..

Posted: Fri Mar 31, 2006 5:38 am
by maztah
i cant say if the pulse timing i programmed is correct. My pulse goes this way, whenever the microcontroller sees a falling edge from the NE signal/pulse, the microcontroller will instantaneously output PW to the injector driver