DIESEL TROUBLESHOOTING WHITE SMOKE
White smoke usually occurs when there is not enough heat to burn the fuel. The unburned fuel particles go out the tailpipe and typically produce a rich fuel smell. It's not unusual to see white smoke in the exhaust during cold weather until the engine warms up.
As mentioned earlier, bad glow plugs or a faulty glow plug control module can cause white smoke on engine start up. Low engine cranking speed may also produce white smoke.
If white smoke is still visible after the engine has warmed up, the engine may have one or more bad injectors, retarded injection timing or a worn injection pump. Low compression can also be a source of white smoke. Air in the fuel system can also cause white smoke.



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