Toyota 4-Runner 1985 Repair Manual page 32

ENGINE MECHANICAL -
Troubleshooting
EM-3
ROUGH IDLING (CONT'D)
Problem Possible cause
Remedy Page
Rough idle, stalls or Engine overheats Check cooling system CO-2
misses (cont'd)
Compression low
Check compression EM-11
Incorrect valve clearance Adjust valve clearance MA-7
ENGINE HESITATES/POOR ACCELERATION
Problem Possible cause Remedy Page
Engine hesitates/ Spark plugs faulty Inspect plugs IG-4
Poor acceleration
High tension wires faulty Inspect wires IG-4
Vacuum leaks Repair as necessary
• PCV hoses
• EGR valve
• Intake manifold
• Air intake chamber
• Throttle body
Pulling in air between air flow meter Repair as necessary
and throttle body
Incorrect ignition timing
Reset timing IG-10
Fuel system clogged
Check fuel system
Air cleaner clogged
Check air cleaner
EF I system problems Repair as necessary
Emission control system problem
(cold engine)
• EGR system always on
Check EGR system
I
Engine overheats
Check cooling system CO-2
Compression low
Check compression
EM-11
ENGINE DIESELING
Problem Possible cause
Remedy
Page
Engine dieseling EFI system problems
Repair as necessary
(run after ignition
switch is turned off)
AFTER FIRE, BACKFIRE
Problem Possible cause
Remedy Page
Muffler explosion Deceleration fuel cut system always
Check EFI (fuel cut) system FI-74
(after fire) on off
deceleration only
Muffler explosion Air cleaner clogged
Check air cleaner
(after fire) all the EFI system problem
Repair as necessary
time
Incorrect ignition timing
Reset timing IG-10
Incorrect valve clearance
Adjust valve clearance
MA-7