Toyota
Jeep Cherokee
 Service Manual
Engine » 4.0L engine » Diagnosis and testing
Cylinder compression pressure test

The results of a cylinder compression pressure test can be utilized to diagnose several engine malfunctions.

Ensure the battery is completely charged and the engine starter motor is in good operating condition.

Otherwise the indicated compression pressures may not be valid for diagnosis purposes.

(1) Clean the spark plug recesses with compressed air.

(2) Remove the spark plugs.

(3) Secure the throttle in the wide-open position.

(4) Disable the fuel system. (Refer to Group 14, Fuel System for the correct procedure) (5) Disconnect the ignition coil.

(6) Insert a compression pressure gauge and rotate the engine with the engine starter motor for three revolutions.

(7) Record the compression pressure on the 3rd revolution. Continue the test for the remaining cylinders.

Refer to Engine Specifications for the correct engine compression pressures.

    More about «Diagnosis and testing»:

    Engine diagnosis-introduction

    Service diagnosis-performance

    Service diagnosis-mechanical

    Intake manifold leakage diagnosis

    Cylinder compression pressure test

    Engine cylinder head gasket failure diagnosis

    Cylinder combustion pressure leakage test

    Engine oil leak inspection

    Engine oil pressure

    Jeep Cherokee Service Manual / Engine / 4.0L engine / Diagnosis and testing / Cylinder compression pressure test

    Jeep Cherokee Service Manual

    Categories


    © 2017-2022 Copyright www.jcherokee.com