2.3L EEC-IV SYMPTOM DIAGNOSTIC

Symptom

Go To: Circuit Test (Step No.)

Engine Runs Rough Or Misses, Lack Of Power, Idle Erratic, RPM Surges, Hesitation ⁽¹⁾

S (2)

Stalls In Self-Test, Engine Stalls

2.3L MA PFI & HSC PFI

S (1)

2.3L OHC PFI

S (2)

Stall During Parking Maneuvers ⁽²⁾

FF (3)

Surges With A/C ON At Idle

KM (30)

A/C Does Not Cut Off Under WOT Condition

KM (15)

A/C Not Functioning

KM (1)

A/C Compressor Runs Continuously ⁽²⁾

KM (35)

Low Idle With A/C On

FA (11)

Stumble After Hot Restart

H (20)

Fuel Pump Runs With Engine Off ⁽³⁾

J (22)

Gasoline Fumes Under Hood ⁽⁴⁾

KD (1)

Black Exhaust Smoke

H (29)

Spark Knock ⁽²⁾

DG (1)

Shift Indicator Light Always On Or Off ⁽⁵⁾

KL (1)

"CHECK ENGINE" Or "SERVICE ENGINE SOON" Light Always On

ML (1)

"CHECK ENGINE" Or "SERVICE ENGINE SOON" Light Never On

ML (5)

"CHECK ENGINE" Or "SERVICE ENGINE SOON" Light On Intermittently

ML (10)

"CHECK ENGINE" Or "SERVICE ENGINE SOON" Light Flashing With Erratic Idle

ML (15)

Trans Will Not Shift Into Overdrive ⁽⁶⁾

⁽⁷⁾ TB (1)

No Trans Lock-Up. Cruise RPM Slightly Higher Than Normal (About 300 RPM) ⁽⁶⁾

⁽⁸⁾ TB

⁽¹⁾	On 2.3L OHC PFI models, verify MAF Sensor is properly connected.

⁽²⁾	Except 2.3L HSC PFI models.

⁽³⁾	2.3L OHC PFI models only.

⁽⁴⁾	Except 2.3L OHC PFI models.

⁽⁵⁾	On 2.3L HSC PFI models only.

⁽⁶⁾	On 2.3L MA PFI models only.

⁽⁷⁾	Use Code 86 Diagnosis.

⁽⁸⁾	Use Code 89 Diagnosis.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

2.3L Symptom-To-Diagnostic Flow Chart Menu

Use the Manual With the Right Hardware

When to See a Mechanic

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