Note. The Assembly Line Data Link (ALDL) connector may also be referred to as the Data Link Connector (DLC). The SERVICE ENGINE SOON (SES) light may also be referred to as the Malfunction Indicator Light (MIL).
Before performing any on-vehicle adjustments to fuel or ignition systems, ensure engine mechanical condition is okay.
VALVE CLEARANCE
Note. All models use hydraulic lifters. No adjustments are required.
4-CYLINDER IGNITION TIMING
| Application | M/T | A/T |
|---|---|---|
| 2.2L (VIN 4) | (1) | (1) |
| (1) Ignition timing is not adjustable (DIS). | ||
| (1) | Ignition timing is not adjustable (DIS). |
4-CYLINDER IGNITION TIMING (DEGREES BTDC @ RPM)
V6 IGNITION TIMING
Note. Ignition timing is not adjustable.
IDLE SPEED & MIXTURE
Note. DO NOT attempt to adjust idle mixture and idle speed. Both are controlled by Powertrain Control Module (PCM). Incorrect idle speeds are normally caused by dirty throttle plate or vacuum leaks. Ensure all vacuum components are functioning properly.
Note. Controlled idle speed and IAC count can be checked using scan tester. See CONTROLLED IDLE SPEED & IAC COUNT table.
Controlled Idle Speed Check
- Ensure no trouble code(s) are present, IAC system is okay, and ignition timing is correct. Block drive wheels. Apply parking brake. Connect Tech 1 scan tester to Data Link Connector (DLC). Put scan tester into OPEN mode.
- Start engine and bring to normal operating temperature. Check for correct state of park/neutral switch on scan tester. Check if idle speed and IAC valve pintle position (counts) are as specified. See CONTROLLED IDLE SPEED & IAC COUNT table.
- If idle speed is not within specification, refer to TESTS W/O CODES article.
| Application | Idle RPM | (1) IAC Counts | |
|---|---|---|---|
| 2.2L SFI | |||
| Auto. Trans. (2) | (3) | (4) | |
| Man. Trans. (3) | (4) | (4) | |
| 4.3L CSI Auto. Trans. (2) | 650 | 5-30 | |
| 4.3L CSI Man. Trans. | |||
| Pickup | 725 | 5-30 | |
| Utility | 700 | 5-30 | |
| (1) Add 2 counts for engines with less than 500 miles. On 4.3L and V8 engines, add 2 counts for every 1000 ft. above sea level. (2) Automatic transmission in Drive. (3) Manual transmission in Neutral. Tech 1 scan tester will display "RDL" with transmission in Neutral. (4) Information not furnished by manufacturer. | |||
| (1) | Add 2 counts for engines with less than 500 miles. On 4.3L and V8 engines, add 2 counts for every 1000 ft. above sea level. |
| (2) | Automatic transmission in Drive. |
| (3) | Manual transmission in Neutral. Tech 1 scan tester will display "RDL" with transmission in Neutral. |
| (4) | Information not furnished by manufacturer. |
CONTROLLED IDLE SPEED & IAC COUNT
THROTTLE POSITION (TP) SENSOR
TP sensor output voltage should be .85 volt or less at idle (closed throttle) and is not adjustable.