Crank No Start Rough Idle or Misfire when Cold due to Compression Loss Hmmm,,, me thinks there is some bad fuel making the rounds!!!! Crank no start when cold condition may affect some customers with GM engines. Models affected: 2000-2009 All GM Passenger Cars with Gasoline Engines 2000-2009 All GM Light Duty Trucks with Gasoline Engines Condition/Concern: Crank no start when cold. The engine may crank over very fast, as if there is low/no compression. It may also run rough for up to 5 minutes after starting the engine and may exhibit a P0300 DTC too. This may be caused by sticking valves due to fuel contamination. When the engine is cold, the compression on multiple cylinders may be at 0 psi. The engine also may pop through the intake or exhaust while cranking and the spark plugs may be fuel fouled when inspected. Some engines may also experience valve damage or cam followers that are out of position as a result of this. This condition will normally occur in specific areas of the country for a period of time and then it will no longer occur after the suspect fuel source has been consumed in that part of the country. Recommendation/Instructions: If the diagnosis indicates to a compression loss due to sticking valves, the following information may help: If there is no sign of valve damage or cam followers that are out of place, perform the following procedure to free up sticking valves and to prevent the valves from sticking again. If valve damage is present or if there are cam followers that are out of place, perform engine mechanical repairs as necessary to correct the concern and then perform the procedure below to prevent the valves from sticking again. 1. Clean the fuel system by following the applicable "Fuel System Cleaning" procedure outlined in service information or appropriate service manual. 2. Add fuel injector cleaner "GM Fuel System Treatment PLUS," p/n 88861011 (for U.S. ACDelcoR, use 88861013) (in Canada, 88861012) 3. Refill the fuel tank using fuel from a high volume, high quality filling station. 4. Clean the induction system using GM Top Engine Cleaner. Follow the directions on the can but DO NOT force the engine to stall since forcing the engine to stall with liquid Top Engine Cleaner could cause the engine to hydro-lock. 5. Advise the customer to change fuel filling stations. They should use fuel from only high volume, high quality filling stations or they should use a Top Tier Detergent Gasoline if available. Note: If the condition is not eliminated chemically, it may be necessary to remove the valves to manually clean the stems. Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed. Some or all of this information was provided by the Automotive Parts Remanufacturers Association (APRA). For more information on technical bulletins available through APRA call 703-968-2772 or visit <http://www.autobulletins.com/> www.AutoBulletins.com. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://list.amc-list.com/pipermail/amc-list-amc-list.com/attachments/20100114/722a0d23/attachment.htm> _______________________________________________ AMC-list mailing list AMC-list@xxxxxxxxxxxx http://list.amc-list.com/listinfo.cgi/amc-list-amc-list.com