EDI TSG-416, Руководство по обслуживанию

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TSG ‐ 416 FUEL SYSTEM
04 ‐ 16
The pinpoint tests below should be performed after the preliminary tests and “Engine Backfires” chart
Steps 1-3. Any electrical diagnostics should have been performed to eliminate any sensor, GCP or
solenoid valve problems before proceeding
Engine Backfires
Test Step Result Action to Take
1 Check for icing or freezing of the regulator. Yes
No
The presence of ice on the
converter with the engine
running, indicates the possibility
of a coolant supply problem.
Check coolant level and the
coolant system for leaks. Check
for proper coolant type.
Go to Step 2.

With the engine at idle

Check for ice or frost build up on the converter
casing and outlet port.
Is ice present?
2 Check DEPR operation.
Yes
No
Possible wiring issue,
faulty ECU, or faulty
DEPR. View page 9 of
this section for wiring
Go to Step 3.

With the engine at idle

Disconnect the electrical connector
Is there a change in engine running with this
unplugged?
3 Check DEPR supply voltage Yes
No
12 volt DEPR circuit is open,
shorted to gnd or the GCP
module is faulty. Check
wiring, connectors and fuses
for possible causes. View
page 9 of this section for
wiring
Go to step 4.

Key OFF

Disconnect DEPR electrical connector

Key ON

Check pins 3 and 6 for 12 volt supply in the harness
Is the voltage less than 11.5 volts?
4 Check the vapor regulator operation
Yes
No
Regulator is
malfunctioning, replace
the regulator.
Go to Step 5.

Engine OFF

Install a pressure gauge on the “Primary Pressure
Test” port

Start and idle the engine
Did you NOT measure 3.5psi?
5
During startup, check for fuel lock leakage (not
closing).
Yes
No
This would indicate the
fuel lock is not closing
and allowing fuel to
pass in the OFF
position. Replace the
fuel lock.
May be electronic, check that the
CAM and crank sensor are not
damaged and as well as all wiring.
Ensure all coils are firing. Check if
faults are present with the GCP
diagnostic software. Refer to section
8, engine controls.

Close the tanks main fuel valve

Install a pressure gauge on the primary test port of
the vapor regulator

Key Off

Slowly open the main fuel valve
Do you measure any fuel pressure?