1999 HONDA CIVIC HO2S

81642 engine:
8 x 1.25 mm
22N,n 12 2 kdl'rn,
Replace.
,&16 rbt.ftl
Replace.
SELF.LOCKING8 x 1.25 mm16 N.m t1.6 kg{ m, 12 lbl'ft)
Replace.
GASKETSReplace.
10 x 1 .25 mm
s4 N.m {5.5 kgf m, 40 lbf'ftl
32.
PIPE A
RePlace'
Remove the damper forks (see section 18).
Disconnect the suspension lower arm ball joints
(see section 18).
Remove the driveshafts.
CAUTION:
o Do not pull on th€ drivoshaft. the CV ioint may
com9 apart.
o Use care whgn prying out the assombly.
Pull it straight to avoid damaging the differential
oil seal or intermediate shaft dust seal.
NoTE: Coat all precision-finished surfaces with
clean engine oil. Tie plastic bags over the driveshaft
enos.
34.
HO2S CONNECTOR
!^.
35.
36.
Lower the hoist.
Remove the upper and lower radiator hoses and
heater hoses,
37. Removs the ATF cooler hoses, then plug the ATF
cooler hoses and PiPes (A,/T)
UPPERRADIATOR HOSE
HOSES
(cont'd)

13. Remove the upper radiator hose' heater hose and
water bYPass hose
WATEREYPASSHOSEUPPERRADIATORHOSE
14.
HEATERHOSE
Remove the engine wire harness connectors and
wire harness clamps from the cylinder head and the
intake manifold.
o Four fuel injector connectors
. Engine coolant temperature (ECT) sensor con-
nector
a
a
a
ECT switch connector
ECT gauge sending unit connector
Throttle position sensor connector
Manitold absolute pressure (MAP) sensor con-
nector
Primary heated oxygen sensor (primary HO2S)
connector
Secondary heated oxygen sensor (secondary
HO2S) connector (D16Y7 engine)
Exhaust gas recirculation (EGR) valve lift sensor
connector (D16Y5 engine)
. VTEC solenoid valve connector (Dl6Y5, D16Y8
engrnes)
. VTEC pressure switch connector (D16Y5. D16Y8
engrnes,
. ldle air control (lAC) valve connector
15.Remove the spark plug caps and distributor from
the cylinder head.
Remove the uPPer bracket.
NOTE:
. Use a jack to support the engine before the
upper bracket is removed.
. Make sure to place a cushion between the oil
pan and the jack.
12 x 1.25 mm
74 N.m {7.5 kgf m.
sil lbl.ftl
UPPERBRACKET
'17. Remove the cylinder head cover'
CYLINDERHEAD COVER
(cont'd)
6-29

WATER BYPASS
HOSE
14. Remove the upper radiator hose, heater hose and
water bvpass hose.
HEATER
Remove the engine wire harness connectors and wlre
harness clamps from the cylinder head and the intake
manifold.
Four fuel injector connector
Engine coolant temperature (ECT) sensor connec-
tor
ECT gauge sending unit connector
ECT switch connector
ldle air control (lAC) valve connector
Manifold absolute pressure (MAP) sensor connec-
tor
Throttle position sensor connector
Primary Heated oxygen sensor (Primary HO2S)
connecror
VTEC solenoid valve connector
15.
a
a
a
a
a
\
16.
17.
Remove the spark plug caps and distributor form
the cylinder head.
Remove the upper bracket.
NOTE:
. Use a jack to support the engine before removing
the upp€r bracket is removed.
. Place a cushion between the oil panandthejack.
12 x 1.25 fin74 N.m 17.5 kgtm,
UPPER BRACKET
18. Remove the cylinder head cover.
{cont'd)
6-69

lntake Manifold/Exhaust System
lntake Manifold
Replacement ....................................... 9-2
Exhaust Manifold
Rep|acement ....................................". 9-6
Exhaust Pipe and Muffler
Replacement ...............................'.'.".. 9-9
Three Way Catalytic Converter {TWCI
Inspection .................."'. 9-12
Heated Oxygen Sensor (HO2SI
Rep|acement ...........................'.."....." 9-12
L_s
r f o

Exhaust Manifold
Replacement
NOTE: Use new gaskets and self-locking nuts when reassembling.
CAUTION:
. Check for folds or scratch€s on the surface of the gasket.
. Replace with a new gasket it damaged.
D16Y5. D16Y7 engines:
I x 1.25 mm24 N.m {2.4 kgt.m, 17 tbtft}
MANIFOLDBRACKET
PRIMARY HEATEDOXYGEN SENSORIPRIMAFY HO2SI44 N.m {4.5 kgf m, 33 lbtft)Replacement, page 9-12
GASKETReplace.
I x 1.25 mm31 N.m (3.2 kgf.m,23 tbf.ft)Beplace.
WAY CATALYTICCONVERTER {TWCIlnspection, page 9'12
6x1.0mm11 N.m {1.1 kgt m,8 lbf.ft)
SECONDARY HEATEDOXYGEN SENSOR(SECONDARY HO2S}44 N.m 14.5 kgf.m,33 lbf.ft)Replacement, page 9-13
9-6

D15Y8 engine:
8 x 1.25 mm2,1 N.m (2.a kgf'm,
17 tbf.ftl
GASKETReplace.
8 x 1.25 mm31 N.m 13.2 kgf'm,23 lbf.ftlReplace.
PRIMARY HO2S44 N.m (4.5 kgf.m, 33 lbtft)Replacement, page 9-13
EXHAUST MANIFOLDBRACKET10 x 1.25 rnm
(cont'd)
9-7
/r4 N.m {4.5 kgf.m, 33 lbf.ft)
v

816A2 engino:
MUFFLER_.,. EXHAUST PIPE
-/- tlP
g
\6r1.omm
9.8 N m 11.0 kgf'm, 7.2 lbl'ttl
GASKETReplace.
8 x 1.25 mm2. N'm 12.2 kgl-m,t6 tbtf0Replace.Tighten the bolts insteps, alternatrngside-to-side.6x1,0mm9,8 N.m 11.07.2lbl4rl
SELF-LOCKING NUTl0 x 1.25 mm
3:t N.m {3.4 kgf m,24lbf'ftl
ReDlace.PRIMARY IIEATEDOXYGEN SENSOR{PRIMARY HO2S)ll N.m (4.5 kgl.m,33 tbt f0Replacement,
SECONDARY HEATEDOXYGEN SENSOR{SECONDARY HO2SIlrt N.m 14.5 kgf.m,33 rbl.ft)Replacement, page 9-13
GASKETR€place.
twcInspection, page 9-12GASKEISReplace.
SELF.L(rcKNG NUT10 x 1.25 mm5,r N.m 15.5 kgf.m, ,|{} lbf.ft)ReDlace.
8x1.25mm22 N.m {2.2 kgt m, 16 lbf.ftlReplsce.Tight6n the bolts in st6ps,alternating side-to-side.8 x 1.25 mm16 N.m 11.6 kgt.m,12 rbf.ft)F€pl8ce.
I
Replaca.
9-11

TWCHO2S
Inspection
l. Using a flashlight, make a visual check for plugging,
melting and cracking of the catalyst.
D16Y5, D16Y7 engines:
816A2, D16Y8 engines:
-\6{-)\
lT
a
A
FLASHLIGI{T
9-12
Replacement
Primary HO2S:
1. Remove the primary HO2S.
D16Y5, D15Y7 engines:
a. Disconnect the primary HO2S connector, thenremove the cover.
8 x'1.25 mm24 N.m {2.4 kgl.m,
PRIMARY H02SCONNECTOR
b. Remove the primary HO2S.
| \l ,l(
I bK/l
l llw.
/
(
PBIMARY HO2S44 N m (4.5 kgf.m, 33 tbI.ft)