Piper Comanche PA-24 Service Manual page 516

Trouble
F u1ure of en&ine to
idle properly.
Low power and uneven
runlliDg.
POWER PLANT
ISSUED: 8118n2
PIPER COMANCHE SERVICE MANUAL
TABLE VlIA-IJI. TltOUBLESHOOTING OIAltT
(ENGINE) (FUEL INJECTOR) (eonc)
c.u.
Rca.dy
Incorrea idle adjustmmt. . .. djust throttle Stop to obtain
correct idle.
~
I IlSUfficimt fuel pressure.
Checlt fuel strainer and pump
pressure adjustment.
Cl~d
injector Doul ...
Remove and f1usb with acetone
Blow through orifice with
compressed air" 100 psi.
Leak in inductioD system.
Tighten all connections in
the induction SYStem. Re-
place any defective pans.
Low cylinder compression. Checlt condition of piston
rinp and valve seats.
F aulry ;,ninon
systms.
Cbeck entire ignition system.
MixtUre too rich; indicar:ed Injector may need recall-
by slugisb e . e opet""
braDon by authOrIZed
aaon, red exhau.st flame
peTSOnDei.
at night. Extreme cues
indicated by blaclt smoke
from exhaust.
Mixture
tOO
lean; indica.ted
Checlt fuel supply. Check
by overheating or baclt"
fuel lines for obsaumons
firing
or rtsmcrions.
Leaky nozzle.
Remoye oozzle and blow
intO
It. Air escaping through
the nozzle valve indicates
"
leaki",. Replace no .. le.
Clogged injector nozzles.
Remove and flush With acetone.
Blow through orifice with
compressed air . 100 psi.
Dirt
in
inlet screen. Remove screen and flush With
acetone. Blow with
compressed air.
DIrt in '," fitting.
Remove 'I" fitemg at
dlStTl·
butor. clean in acetone.
Blow through orifice With
compressed aU"· 100 psi.
Fuel supply pressure Check ruel pump pressure.
excessively high.
Leak In manifold line Tl!hten
finin~.
2 E14