Toyota 4-Runner 1985 Repair Manual page 36

ENGINE MECHANICAL - Troubleshooting EM-7
ENGINE DIESELING
r
Problem Possible cause Remedy Page
Engine dieseling Carburetor problems Repair as necessary FU-4
(runs after ignition
• Linkage sticking
switch is turned off)
• Idle speed or fast idle speed out
of adjustment
• Fuel cut solenoid faulty
Incorrect ignition timing Reset timing IG-l0
EGR system faulty Check EGR system EC-30
AFTER FIRE, BACKFIRE
Problem
Possible cause Remedy
Page
Muffler explosion AS system faulty C heck AS system
EC-43
(after fire) on
MC system faulty
Check MC system EC-26
deceleration only
Deceleration fuel cut system always
Check fuel cut system
EC-63
off
Muffler explosion Air filter clogged Check air filter MA-5
(after fire) all the
Choke system faulty Check choke
EC-55
time
Incorrect ignition timing Reset timing IG-10
Incorrect valve clearance Adjust valves clearance
MA-7
Engine backfires Choke valve open (cold engine) Check choke system
EC-55
Carburetor vacuum leak
Check hoses and repair as
necessary
Insufficient fuel flow
Troubleshoot fuel system FU-2
Incorrect ignition timing Reset timing
IG-l0
Incorrect valve clearance Adjust valve clearance
MA-7
Carbon deposits in combustion
Inspect cylinder head
EM-18
chambers
EXCESSIVE OIL CONSUMPTION
Problem Possible cause
Remedy Page
Excessive oil Oil leak
Repair as necessary
consumption
PCV line clogged
Check PCV system
EC-19
Piston ring worn or damaged Check rings
EM-57
Valve stem and guide worn Check valves and guides
EM-19
Valve stem oil seal worn or damaged
Check oil seal