Mechanics

MISFIRES ON 456 AFTER REBUILD

1999 Porsche 911

Engine Mechanical problem
1999 Porsche 911 6 cyl Two Wheel Drive Automatic 75000 miles

Car overheated and cracked the 456 head.123 checked out fine, replaced the head, new gaskets, torques correctly etc. Engine has a misfire/not running on the 456 bank, 123 sound fine. Compression is 175 on all 6, pulled the fuel rail and watched good spray from injectors, coils have a good spark. When installed the cams I used the special Porsche chain tensioning tools on the intermediate and cam shaft chains, the cam sensors are pointing in there correct positions, the cam gear marks are up while at tdc on both banks, the coil wires and injector wires are all correct. I'm thinking it's some type of timing issue please give me your input. One thing I thought of today. Was I supposed to rotate the engine before I installed bank456 head? My Manuel is really unclear regarding the installation procedure of the heads. Thanks for your time
Avatar
Sureshot66
January 18, 2010.




Ok first off lets check the cams and the chain placement. Here is how the cams should be lined up and then the next pic shows how the colored links should be lined up with the cam dots. Let me know if this is good.

Cam alignment,


http://www.2carpros.com/forum/automotive_pictures/249564_Graphic_188.jpg



Chain placement


http://www.2carpros.com/forum/automotive_pictures/249564_Graphic1_30.jpg


Racefan966
Jan 20, 2010.


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