Exhaust Restriction Diagnosis/Repair (TS 4-07 02159(R))

Publication date: 1970-01-01
Reference number: TS 4-07 02159(R)

EXHAUST RESTRICTION DIAGNOSIS/REPAIR

TECHNICAL SERVICE BULLETIN

Reference Number(s): TS 4-07 02159(R), Date of Issue:

EXHAUST RESTRICTION DIAGNOSTIC PROCEDURE

Model(s): ALL SAMURAI

Bulletin No.: TS 4-07 02159(R)

Group: Engine Performance

SERVICE INFORMATION

To identify a restricted exhaust condition on a vehicle, perform the following test.

With the engine off, disconnect the oxygen sensor connector, located on the left fender panel. (See Fig 1 ).

Fig 1: Oxygen Sensor View
With the engine off disconnect and plug the vacuum line leading to the EGR valve from the TWSV. (See Fig 2 ).

Fig 2: EGR Plug View
Disconnect the large hose leading to the base of the EGR modulator from the EGR valve, and insert a fuel pump pressure gauge. With the engine running at normal operating temperature and not under load, observe the gauge reading at 2,500 rpm. If the back pressure exceeds 2.8 psi, an exhaust restriction is indicated.

The exhaust restriction may be due to a collapsed header pipe, internal center pipe failure, internal muffler failure, or a damaged tailpipe. Replace parts as necessary to complete the repair.