1991 Nissan D21 P0421 Fault Code Check

When you check 1991 Nissan D21 car engine light came on code P0421 the reason should be Engine Light ON (or Service Engine Soon Warning Light). However Nissan manufacturer may have a different definition for the P0421 OBD-II Diagnostic Powertrain (P) Trouble Code. So you should chech it on our car models.

To solve P0421 1991 1991 Nissan D21 problem, you'll have to remove the muffler, crankcase and other components blocking the valve chamber. Then, remove the cylinder head bolts (label for easy re-installation) Adjust the jaws of the valve spring compressor until they touch the top and bottom of the valve chamber Push the tool in to compress the spring and tighten the jaws Remove the retainers and lift out the valves , compressors and springs

1991 Nissan D21 P0421 OBD-II Diagnostic Powertrain (P) Trouble Code Description 1991 Nissan D21 car P0421 OBD-II Trouble Code The Engine Control Module ( Reason For 1991 Nissan D21 P0421 Code The reason of 1991 Nissan D21 P0421 OBD-II Fault Code Check is P0421 Warm Up Catalyst Efficiency Below Threshold Bank 1.

1991 Nissan D21 P0421 Possibble Fix Ways :

The engine relies on the glow plugs to generate heat to help with the combustion cycle. Some engines only use the glow plugs when cold but others will allow the glow plugs to work when the ECU (vehicle's computer) needs them to be on to help with combustion. Problems in this area will cause diesel engine starting problems, uneven running and white smoke when the engine is cold.

If your vehicle failed a P0421 1991 1991 Nissan D21 test and the P0421 Check Engine Light is NOT on, chances are you have a problem with the OBDII system, a burned out MIL lamp, or a faulty catalytic converter. The converter is essentially an afterburner that cleans up the exhaust after it exits the engine. The OBDII system uses P0421 a ownstream oxygen sensor to monitor the efficiency of the converter, and it should detect a drop in converter efficiency if the converter has been contaminated or is failing (ignition misfiring, leaky exhaust valves, and oil burning can all damage the converter). What you want to look P0421 1991 1991 Nissan D21: Any conditions that might cause ignition misfire, an overly rich or lean fuel condition, or loss of compression.

What does fault code P0421 mean for 1991 Nissan D21 ? What does a diagnostic reading P0421 mean for 1991 Nissan D21 ? How to fix OBD2 Code P0421 for 1991 Nissan D21 ? What do we know about P0421 code for 1991 Nissan D21 ?