Accel/dfi – Mallory Ignition ACCEL CHEVROLET APPLICATIONS (including LT-1) 74022 User Manual

Page 12

ACCEL/DFI

The following are some common problems we have encoun-
tered with various installations.

Injectors not firing (clicking) - the vehicle will not start:

• Usually due to a low battery. Voltage must be

above nine volts during cranking to activate
the ECM.

• Injector harness not connected to the main

wiring harness.

• Short in either pin P1-C7 or P1-C8. Check

continuity to battery positive and negative
wires with an OHM meter.

• Tach wires to positive side of coil instead of

negative.

• P1-D7 (long pink wire with female spade

connector) not receiving 12 volts during
cranking. Usually due to connecting this
wire to a voltage source that is disabled
during cranking.

Runs rich at idle:

• Vacuum line to fuel pressure regulator not

connected.

• MAP sensor vacuum line pinched.

• UIM idle knob turned all one way.

Runs rich all the time:

• Wrong injectors for the application.

• Return fuel line is too small/restricted.

• Calibration in the ECM is wrong for the

application.

Engine cranks a while before starting:

• +12V and ground terminals not connected

directly to battery.

• Fuel pump is not priming the fuel system.

If you are experiencing problems please contact your
ACCEL dealer or feel free to contact ACCEL’s technical
service line and talk to an ACCEL/DFI technical representative.
ACCEL’s technical phone number is: 1.216.398.8300 EXT: 500.

Written by Charlie Trombley

XIII – TROUBLE SHOOTING GUIDE