N-912-317-01 Genuine VW/Audi Turbocharger Mounting Stud - M8 x 25

Genuine VW/Audi turbocharger mounting stud, part number N-912-317-01. This original threaded fastener is used at the turbocharger mounting flange-to-cylinder-head connection on the confirmed configurations below. One stud is supplied.

Technical details

• Original number: N-912-317-01 / N91231701.
• Published nominal specification: M8 x 25.
• Double-ended threaded stud with a central unthreaded section, as pictured.
• Application: turbocharger mounting flange connection at the cylinder head.
• Mounting nuts, flange gasket and other installation hardware are separate.

The stud provides the threaded mounting connection used with the specified nut to retain the turbocharger flange. The fastener, flange, gasket and remaining hardware must all match the engine's mounting arrangement. The published M8 x 25 designation is a nominal catalog specification; it is not a complete dimensional drawing of both threaded ends.

This part is distinct from turbo support bracket bolts, downpipe connection hardware and oil or coolant line fasteners. An adjacent attachment may use different threads, lengths or tightening requirements. Select the original number for the exact flange position being serviced.

Common reasons to replace

Inspect the studs when removing or replacing the turbocharger or servicing the flange gasket. Replace a stud with damaged threads, breakage, bending or corrosion that prevents correct assembly. A stud that is missing or has been replaced with incorrect hardware also requires attention.

Threads damaged during nut removal can prevent normal engagement of the replacement nut. Check both the stud and the nut rather than forcing the connection. Follow the factory service requirements for renewing studs, nuts and sealing components during the repair.

A leak or abnormal noise near the turbo mounting flange requires diagnosis of the entire connection. A new stud does not repair a cracked flange, damaged cylinder-head threads, a failed turbocharger or an improperly seated gasket. Correct the diagnosed fault and inspect the mating components before reassembly.

Installation and service notes

Follow the factory turbocharger removal and installation procedure for the exact engine. Allow the turbocharger and exhaust components to cool and support the assembly as directed. Keep contamination out of any opened intake, oil and coolant connections during service.

Identify the mounting position and compare the original number before fitting replacement hardware. Inspect the threaded hole and flange for damage. Where the original stud has broken, use an appropriate repair procedure that protects the cylinder-head threads and sealing surfaces.

Install the stud to the engagement specified by the factory procedure, then position the required gasket and turbocharger correctly. Do not use mounting nuts to pull an improperly aligned assembly into place. Obtain the prescribed nuts and remaining installation components separately.

Follow the engine-specific tightening sequence, thread preparation and hardware renewal instructions. Do not substitute a general M8 torque value or a specification from another exhaust connection. Lubricant or thread treatment should only be used where the repair procedure prescribes it.

After installing the turbocharger, complete all required checks for the flange and any disturbed oil, coolant, intake or exhaust connections. Confirm the support bracket and remaining mounting hardware are correctly fitted before returning the vehicle to service.

Fitment

Confirm N91231701 at the original turbocharger mounting flange. One stud supplied.