Engine Controls - Basic Testing - 2.7L: Diagnosis Toyota T100 I

VISUAL INSPECTION

Visually inspect all electrical wiring, looking for chafed, stretched, cut or pinched wiring. Ensure electrical connectors fit tightly and are not corroded. Ensure vacuum hoses are properly routed and are not pinched or cut. See the VACUUM DIAGRAMS article to verify routing and connections (if necessary). Inspect air induction system for possible vacuum leaks.

SPARK TEST

1. Disconnect spark plug wires. Remove spark plugs. Install spark plug on each spark plug wire. Ground spark plug against cylinder block. CAUTION: To prevent gasoline from being injected, DO NOT crank engine for longer than 2 seconds.
2. Crank engine and check for spark. If spark does not occur, check ignition coil, ignitor and distributor electrical connections.
3. If electrical connections are okay, using ohmmeter, check resistance of spark plug wire. Replace spark plug wire if resistance is not within specification. See «SPARK PLUG WIRE RESISTANCE SPECIFICATIONS»(ref-21581-S38113487732001010300000) table. If resistance is within specification, proceed to step 4). SPARK PLUG WIRE RESISTANCE SPECIFICATIONS Application Maximum Ohms T100 4-Cyl 25,000 Per Wire
4. Check voltage at ignition coil and ignitor. Turn ignition on. Ensure voltage exists at ignition coil positive terminal. If voltage exists, proceed to step 5). If voltage does not exist, check wiring between ignition switch, ignition coil and ignitor. See wiring diagram in the WIRING DIAGRAMS article.
5. Check ign. coil resistance. See «IGNITION COIL RESISTANCE»(ref-21581-S10817432442001010300000) . Replace ignition coil if resistance is not within specification. If ignition coil resistance is within specification, proceed to step 6).
6. Check pick-up coil resistance. See procedures under «PICK-UP COIL RESISTANCE»(ref-21581-S35572288262001010300000) . Replace pick-up coil or distributor assembly if pick-up coil resistance is not within specification. If pick-up coil resistance is within specification, proceed to next step.
7. Check resistance of crankshaft position sensor. See «CRANKSHAFT POSITION SENSOR»(ref-21581-S19136064852001010300000) . If crankshaft position sensor is okay, proceed to next step.
8. Check pick-up coil air gap. See «PICK-UP COIL AIR GAP»(ref-21581-S01129409642001010300000) . If pick-up coil air gap is incorrect, replace distributor assembly. If pick-up coil air gap is correct, proceed to step 9).
9. Check ignition IGT signal from Engine Control Module (ECM). If ignition IGT signal from ECM is defective a diagnostic trouble code will be set in the ECM memory to indicate a ignitor circuit malfunction. See the TESTS W/CODES article for diagnostic trouble code. If IGT signal is okay, substitute another ignitor and recheck system operation.