Converter

Tiny
PATACAKE
  • MEMBER
  • 2004 NISSAN SENTRA
  • 4 CYL
  • 2WD
  • AUTOMATIC
  • 260,000 MILES
On code po420 cat. Converter, does that mean you need to replace your converter? Or could something eles be wrong, I hate to spend money on a converter and thats not the problem, is there any way you can make sure its the converter?
Do you
have the same problem?
Yes
No
Thursday, March 31st, 2011 AT 11:11 AM

1 Reply

Tiny
KHLOW2008
  • EXPERT
DIAGNOSTIC PROCEDURE

1. CHECK EXHAUST SYSTEM

Visually check exhaust tubes and muffler for dent.
OK or NG
OK: GO TO 2.
NG: Repair or replace.

2. CHECK EXHAUST GAS LEAK
a) Start engine and run it at idle.
B) Listen for an exhaust gas leak before the three way catalyst (manifold).

OK or NG
OK: GO TO 3.
NG: Repair or replace.

3. CHECK INTAKE AIR LEAK

a) Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK: GO TO 4.
NG: Repair or replace.

4. CHECK IGNITION TIMING

a) Check for ignition timing.
OK or NG

OK: GO TO 5.
NG: Follow the BASIC INSPECTION.

5. CHECK INJECTORS

a) Stop engine and then turn ignition switch ON.

B) Check voltage between ECM terminals 22, 23, 41, 42 and ground with tester.

C) Battery voltage should exist.

OK or NG
OK: GO TO 6.
NG: Perform Diagnostic Procedure

6. CHECK IGNITION SPARK

a) Turn ignition switch OFF.
B) Disconnect ignition coil assembly from rocker cover.
C) Disconnect all injector harness connectors.
D) Connect a known-good spark plug to the ignition coil assembly.
E) Place end of spark plug against a suitable ground and crank engine.
F) Check for spark.

OK or NG
OK: GO TO 7.
NG: Check ignition coil with power transistor and their circuit.

7. CHECK INJECTOR

a) Turn ignition switch OFF.
B) Remove injector assembly.
Keep fuel hose and all injectors connected to injector gallery.
C) Reconnect all injector harness connectors.
D) Disconnect all ignition coil harness connectors.
E) Turn ignition switch ON.
Make sure fuel does not drip from injector.

OK or NG
OK (Does not drip): GO TO 8.
NG (Drips): Replace the injector(s) from which fuel is dripping.

8. CHECK INTERMITTENT INCIDENT
Perform TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT.

Trouble is fixed: INSPECTION END

Trouble is not fixed: Replace three way catalyst (manifold).
Was this
answer
helpful?
Yes
No
Thursday, March 31st, 2011 AT 5:34 PM

Please login or register to post a reply.

Recommended Guides