Engine Controls - Lack Of Power On Acceleration

Classification:
EF&EC93-006

Section:
Engine Fuel & Emissions Control

Models:
1992-3 Maxima (J30)

Reference:
TECHNICAL BULLETIN NTB93-116

Date:
August 3, 1993

ENGINE LACK OF POWER ON ACCELERATION
MAXIMA (J30) WITH VE30DE ENGINE

APPLIED MODELS:
1992-3 Maxima (J30) with VE30DE Engine

SERVICE INFORMATION:

Some manual transmission vehicles may exhibit a perceived lack of power between 3,500 RPM and 5,000 RPM under wide open throttle (WOT) acceleration in 2nd or 3rd gear.

Some automatic transmission vehicles may exhibit a similar perceived lack of power on wide open throttle (WOT) acceleration from a standing start.

This may be due to the timing map in the ignition control or knock sensor control circuits of the Engine Electronic Control Module Assembly.

NOTE:
For maximum engine performance, you may recommend that customers use "Premium Unleaded" gasoline in their vehicles.

EVALUATION PROCEDURE:

1. Warm engine until it reaches operating temperature 95 degrees Celsius (203 degrees Fahrenheit). Turn off the engine.

2. Attach CONSULT to the DDL connector, with the key in the "off" position.

3a. Vehicles with Manual Transmission:
1. Start the car, turn CONSULT "On". Touch START. Select ENGINE; touch MAIN SIGNALS; touch DATA MONITOR.
2. Monitor MAIN SIGNALS, while driving, paying attention to IGN TIMING.
3. Accelerate in 3rd gear from 3,500 to 5,000 rpm, under wide open throttle (WOT).

3b. Vehicles with Automatic Transmission:
1. Start the car, turn CONSULT "On". Touch START. Select ENGINE; touch MAIN SIGNALS; touch DATA MONITOR.
2. Monitor MAIN SIGNALS, while driving, paying attention to IGN TIMING.
3. Accelerate in "D1" at wide open throttle (WOT) from a standing stop.
4. Repeat Steps 3a. or 3b., as appropriate - for Manual Transmission or Automatic Transmission-equipped vehicles, five (5) times and check the "IGN TIMING" on the "DATA MONITOR" mode of CONSULT. The ECM Knock Sensor circuit sensitivity requires five (5) hard wide open throttle (WOT) acceleration tests to duplicate the incident.

NOTE:
If data shows that "IGN TIMING" reads 3 degrees BTDC or less on either acceleration test, install Engine Sub-Harness, P/N 24020-7E060, at Knock Sensor Sub-Harness connector (see PARTS INFORMATION).

5. Access "ACTIVE TEST" using CONSULT and clear "SELF LEARNING CONT".
6. Road test vehicle to verify effectiveness of repair as per Steps 3a or 3b, as appropriate.
7. If ignition timing continues to retard, it will be necessary to replace the Electronic Control Module Assembly, [see PARTS INFORMATION].

PARTS INFORMATION:

Description NEW Part Number OLD Part Number APPLIED for

Harness, Engine Sub- 24020-7E060 n/a All J30
Band, Clamp 01552-00411 n/a All J30

Module Assembly, 23710-7E210 23710-97E00 M/T; Federal
Engine Control
23710-7E215 23710-97E10 A/T; Federal
23710-7E110 23710-97E05 M/T; Calif.
23710-7E115 23710-97E15 A/T; Calif.

WARRANTY INFORMATION:

For Replacement of Sub-Harness, ONLY

Operation OpCode PNC CS CT FRT

Repair EFI Harness DE38AA 24011 1R 38 0.3 hrs.

For Replacement of Sub-Harness AND Electronic Control Module

Operation OpCode PNC CS CT FRT

Rpl EFI Control Unit DE28AA 22611 1R 38 0.4 hrs.
Repair EFI Harness DE38AA 0.3 hrs.