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Service bulletin IB12-J-005D

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id10181749
Published by NHTSA2020-10-26
Manufacturer's numberIB12-J-005D
Manufacturer's date2020-09-29
NHTSA componentENGINE; EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT

NHTSA's summary

WHEN REPLACING AN ENGINE DUE TO INTERNAL DAMAGE, EXTREME CARE SHOULD BE TAKEN WHEN TRANSFERRING THE INTAKE MANIFOLD TO THE ENGINE LONG BLOCK. THE INTERNAL ENGINE DAMGE MAY HAVE RESULTED IN THE POTENTIAL DISCHARGE OF INTERNAL ENGINE COMPONENT DEBRIS INTO THE INTAKE MANIFOLD VIA BROKEN PISTONS AND/OR BENT, BROKEN, OR MISSING INTAKE VALVES. AFTER REMOVING THE INTAKE MANIFOLD FROM THE ENGINE, THE TECHNICIAN MUST CAREFULLY INSPECT ALL OF THE CYLINDER HEAD INTAKE PORTS TO SEE IF THE VALVE HEADS ARE STILL PRESENT AND NOT BENT. USUALLY WHEN THE VALVE HEADS ARE MISSING OR SUFFICIENTLY BENT, INTERNAL ENGINE COMPONENT DEBRIS WILL BE PRESENT TO VARYING DEGREES IN TEH INTAKE PORT OF THE CYLINDER HEAD. IF THIS DEBRIS IS PRESENT IN ANY OF THE CYLINDER HEAD PORTS, THE INTAKE MANIFOLD SHOULD BE REPLACED. THIS REPLACEMENT IS REQUIRED DUE TO THE COMPLEX INLET RUNNER AND PLENUM CONFIGURATION OF MOST OF THE INTAKE MANIFOLDS, MAKING THOROUGH AND COMPLETE CLEANING DIFFICULT AND NEARLY IMPOSSIBLE TO VERIFY THE COMPLETE REMOVAL OF DEBRIS. REINSTALLATION OF AN INTAKE MANIFOLD REMOVED FROM AN ENGINE WIHT DEPOSITS OF INTERNAL ENGINE COMPONENT DEBRIS, MAY RESULT IN THE INGESTION OF ANY REMAINING DEBRIS INTO THE NEW SERVICE ENGINE. THIS WILL CAUSE DAMGE OR POTENTIAL FAILURE OF THE NEW SERVICE ENGINE LONG BLOCK.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Engine, Equipment and accessories

Vehicles listed
ISUZU N SERIES

Listing a model year does not mean every vehicle of it is concerned: the document says which.