<TABLE style="WIDTH: 598pt; BORDER-COLLAPSE: collapse" cellSpacing=0 cellPadding=0 width=797 border=0 x:str><COLGROUP><COL style="WIDTH: 598pt; mso-width-source: userset; mso-width-alt: 29147" width=797><TBODY><TR style="HEIGHT: 12.75pt" height=17><TD class=xl25 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 598pt; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" width=797 height=17>Causes of Coking (TSB 08-2-7); DETERMINE THE ROOT CAUSE:</TD></TR><TR style="HEIGHT: 25.5pt" height=34><TD class=xl25 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 598pt; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 25.5pt; BACKGROUND-COLOR: transparent" width=797 height=34>Un-combusted fuel is usually evident as fuel scented white exhaust smoke. Un-combusted fuel may create coking which impairs system functionality eventually leading to black exhaust smoke/poorly combusted fuel. Engine oil can also be the source of coking. The source can not be determined visually.</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl26 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 598pt; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" width=797 height=17>Specific Causes:</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 598pt; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" width=797 height=17 x:str="'- Poor fuel - replace with good fuel and use a good fuel additive (Stanadyne Performance Formula or Ford PM-22-A or PM-23-A)">- Poor fuel - replace with good fuel and use a good fuel additive (Stanadyne Performance Formula or Ford PM-22-A or PM-23-A)</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 598pt; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" width=797 height=17 x:str="'- Excessive idling">- Excessive idling</TD></TR><TR style="HEIGHT: 25.5pt" height=34><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 598pt; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 25.5pt; BACKGROUND-COLOR: transparent" width=797 height=34 x:str="'- Excessive fuel (note fuel pressure must be kept over 45 psig, to avoid injector damage). Check for DTC's, injector problems could cause excessive fuel flow.">- Excessive fuel (note fuel pressure must be kept over 45 psig, to avoid injector damage). Check for DTC's, injector problems could cause excessive fuel flow.</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 598pt; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" width=797 height=17 x:str="'- Engine oil: thickened engine oil and poor maintenance can delay commanded injector response, caused by wrong oil viscosity or excessive OCI.">- Engine oil: thickened engine oil and poor maintenance can delay commanded injector response, caused by wrong oil viscosity or excessive OCI.</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 598pt; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" width=797 height=17 x:str="'- Engine oil: oil carryover to air inlet system caused by restricted air filter element pulling in oil from ccv, high crankcase pressure, or turbo oil leak.">- Engine oil: oil carryover to air inlet system caused by restricted air filter element pulling in oil from ccv, high crankcase pressure, or turbo oil leak.</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 598pt; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" width=797 height=17 x:str="'- Excessive EGR flow. Correct with newer flash or check for bad EGR valve and correct.">- Excessive EGR flow. Correct with newer flash or check for bad EGR valve and correct.</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 598pt; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" width=797 height=17 x:str="'- Delayed injection event caused by FICM wire chaffing, FICM calibration, or injector mechanical issues.">- Delayed injection event caused by FICM wire chaffing, FICM calibration, or injector mechanical issues.</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 598pt; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" width=797 height=17 x:str="'- The most recent calibration flash will help reduce coking deposit formation by improving:">- The most recent calibration flash will help reduce coking deposit formation by improving:</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl27 style="BORDER-RIGHT: #d4d0c8; BORDER-TOP: #d4d0c8; BORDER-LEFT: #d4d0c8; BORDER-BOTTOM: #d4d0c8; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" height=17>

• Shut off EGR after 5 minutes of idling. Reduces the amount of hard to combust elements in the combustion chamber.

</TD></TR><TR style="HEIGHT: 25.5pt" height=34><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 598pt; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 25.5pt; BACKGROUND-COLOR: transparent" width=797 height=34 x:str="Injection timing improvements at 1100-1800 RPM (Typical range for PTO operation/Cold Ambient Protection Idle Kicker/Battery Charge Protect Idle Kicker). ">

• Injection timing improvements at 1100-1800 RPM (Typical range for PTO operation/Cold Ambient Protection Idle Kicker/Battery Charge Protect Idle Kicker).

</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 598pt; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" width=797 height=17>

• Increased exhaust pressure / VGT Duty Cycle for APCM or PTO commanded engine speeds. Maintains heat in the combustion chamber.

</TD></TR><TR style="HEIGHT: 25.5pt" height=34><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 598pt; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 25.5pt; BACKGROUND-COLOR: transparent" width=797 height=34 x:str="Higher engine temperature required for cold ambient idle kicker to switch off. Idle will remain elevated until driver input is observed by powertrain control module (PCM). Maintains heat in the combustion chamber. ">

• Higher engine temperature required for cold ambient idle kicker to switch off. Idle will remain elevated until driver input is observed by powertrain control module (PCM). Maintains heat in the combustion chamber.

</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl24 style="BORDER-RIGHT: windowtext 0.5pt solid; BORDER-TOP: windowtext; BORDER-LEFT: windowtext 0.5pt solid; WIDTH: 598pt; BORDER-BOTTOM: windowtext 0.5pt solid; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" width=797 height=17 x:str="Improved EGR throttle plate self test. Better control of hard to combust elements. ">

• Improved EGR throttle plate self test. Better control of hard to combust elements.

</TD></TR></TBODY></TABLE>

 

Nice post. I guess it is safe to say that heavily tuned smokers need to watch out?