Suzuki Samurai 1986, Service Manual

Page: 189 / 482

EXHAUST GAS RECIRCULATION (EGR)
SYSTEM
Checking EGR system
NOTE:
Before checking, confirm that altitude is not
higher than 1,220 m (4,000 (atmospheric
pressure is below 680mmHg) and gear shift
lever is at neutral position.
When performing this check at higher than
1,220 m (4,000 ft) altitude, be sure to dis-
connect HAC coupler.
Run engine when it is cool (coolant tempe-
rature is below 55°C (131°F)) and check
that EGR valve diaphragm is not operating in
this state, by touching diaphragm with
finger.
WARNING:
If EGR valve is hot, it may be necessary to
wear gloves to avoid burning finger.
2
2. Diaphragm
Fig. 5-3-50 Checking EGR valve diaphragm
2) Warm up engine to normal operating tempe-
rature and race it after warming up. Then
check to be sure that diaphragm moves
toward in below figure during acceleration
and toward during deceleration.
During acceleration
2. During deceleration
3. Diaphragm
Fig. 5-3-51 Movement of EGR valve diaphragm
If found defective in above step 1) or inspect
following parts according to each procedure.
NOTE:
Refer to item “CHECKING SENSOR AND
THEIR LEAD WIRES” in page 5-32 for check-
ing HAC, fifth switch and their circuit.
[Vacuum hoses]
Check hoses for connection, leakage, clog and
deterioration. Replace as necessary.
valve]
1) Disconnect vacuum hose from TWSV.
2) Connect vacuum pump gauge to its hose.
3) Check that EGR valve diaphragm moves
smoothly and that it is held at the same
position when more than 20 vacuum
is applied to EGR valve.
If diaphragm doesn’t move smoothly, or it
isn’t held at the same position, replace EGR
va Ive.
1. Apply vacuum
2. No vacuum
3. Diaphragm
4) After checking, be sure to connect vacuum
hose to TWSV.
5-37