MK5 GTI EA113 Oil Filter Housing: Replace the Housing and Refill Both Circuits

Bottom line: A complete EA113 oil-filter-housing repair with intake and boost-pipe access, oil-cooler removal, pressure-switch transfer, housing installation, oil priming and coolant burping.

Repair at a glance

Field	Repair detail
Applies to	EA113 FSI layouts in listed Mk5-era VW/Audi vehicles after part-number confirmation
Repair trigger	Verified front-engine leak from a warped housing or failed housing seal
Parts	Complete housing, cooler seal, filter, cap seal, coolant and optional brittle PCV hose
Time / difficulty	Several hours; intermediate because most housing bolts are reached by feel
Stop point	Oil-pressure switch thread or block sealing face is damaged
Proof complete	Immediate oil pressure, stable coolant, dry housing and cooler after cold recheck

Confirm the repair before disassembly

The EA113 housing sits low at the radiator side of the engine, so oil spreads over the splash shield and nearby connections. Clean the area and confirm fresh oil begins at the housing-to-block or cooler-to-housing seam. A leaking vacuum pump, filter cap or spilled service oil can create a similar lower-engine pattern.

Inspect the plastic housing for warping and cracks rather than automatically fitting only a seal. Check the PCV hose that connects to it; the connector often becomes brittle in the same heat that hardens the housing seal. Use the oil-leak source tracing workflow if the highest fresh point is uncertain.

Parts, tools, and consumables to stage

Stage the complete job before access is opened. Part numbers, seals, bolt-reuse rules and fluid specifications must be matched to the VIN, engine or chassis code; a familiar model name is not precise enough.

Parts and consumables	Tools and support equipment
• VIN-correct complete oil filter housing • Oil-cooler seal and oil-filter element with cap O-ring • PCV/breather hose if the aged connector will not survive removal • Throttle-body seal if it is flat or hard • Specified engine oil and coolant • Oil-pressure switch only if its body, pins or threads fail inspection	• 36 mm filter-cap socket • 10 mm and 7 mm sockets • 5/6 mm hex-bit and M6 triple-square sockets • T25 and T30 bits • 24 mm wrench for the pressure switch • Hose-clamp pliers, picks, extensions and low-range torque wrench • Two-fluid drain pans or clearly separated containers

Preparation and safety boundary

Start cold. Support the car at approved points before the lower boost pipe or splash shield is touched. Keep oil and coolant in separate labeled pans. Never open the hot expansion tank, and clean any spill from the belt and tire path before the engine runs.

Disconnect the battery negative if service data calls for it around the starter or wiring path. Protect throttle openings and charge pipes from debris. Electrical connectors at the throttle body, MAP sensor and oil-pressure switch need their locks released; pulling by the wire can create an intermittent fault after an otherwise correct mechanical repair.

Remove the access layers without losing the map

Remove the intake snorkel, disconnect the MAF, release the turbo-inlet clips and lift the engine-cover airbox from its four grommets. Disconnect both throttle-body plugs and the MAP sensor. Remove the induction-noise pipe, loosen the 7 mm throttle hose clamp and remove the lower splash shield.

At the intercooler, release the boost-pipe lock and its T30 mount, then pull the pipe off its stud and remove it downward. Remove the four T30 throttle-body fasteners and support the body. Above the cooler, move the coolant-pipe bracket, then release the aged PCV hose and the M6 triple-square harness bracket.

Use separate trays for each access layer, label connectors by destination and photograph every hidden hose before it moves. Mark fastener length and location on a drawn component outline. Reassembly should follow a map created during removal, not memory or wire reach.

Exact repair sequence

Complete the following sequence in order. A bold lead identifies the action; the remaining sentence states the checkpoint that must be true before the next action begins.

1. Drain coolant deliberately. Open the expansion-tank cap only when cold, place the coolant pan, release the after-run-pump hose and control the flow. Reconnect or plug the hose once drained.
2. Drain the filter housing. Remove the lower housing cap and push the orange drain valve upward. Let the housing empty, then return the valve to its seated position.
3. Remove the oil cooler. Use a 6 mm hex bit on the four cooler fasteners, two above and two below. Support the cooler, break its seal and release the remaining coolant hose over the pan.
4. Find all four housing bolts by touch. Use a 10 mm socket or the correct hex drive. Clean the bolt heads so the tool seats fully, then loosen the fasteners in stages.
5. Free the housing from the block. Move the adjacent coolant line only enough to create clearance. As the housing comes upward, disconnect the oil-pressure switch before pulling the assembly out.
6. Transfer the pressure switch. Hold the old housing securely, remove the switch with a 24 mm wrench and inspect its threads and sealing method. Install it in the new housing to the specified orientation.
7. Clean the block face. Apply cleaner to a wipe, not into the openings. Remove oil, coolant and gasket residue without gouging the aluminum or leaving lint in an oil passage.
8. Create installation clearance. Remove the adjacent bracket with a 6 mm hex only if required. Route the new housing through the coolant-line gap without loading its plastic neck.
9. Reconnect the pressure switch before seating. Once the connector clicks, position the housing and start all four bolts by hand. If a bolt will not turn freely, stop and realign rather than pulling the housing in crooked.
10. Torque the housing evenly. On the documented EA113 configuration, housing bolts and oil-pressure switch are 15 Nm. Verify the switch sealing method and torque for the installed part number.
11. Prepare and install the cooler. Clean its face, fit the new seal, reconnect the coolant hose and start all four bolts. Tighten evenly to 15 Nm on the documented configuration.
12. Restore the air path. Replace a hard throttle seal, install the throttle body, boost pipe, MAP connector, induction-noise pipe, PCV hose, engine-cover airbox, MAF and intake snorkel in the recorded order.

Reassembly and torque control

Before the lower shield returns, verify that every boost-pipe lock is fully engaged, every hose clamp sits behind its bead and the PCV hose clicks at both ends. Refit all moved harness brackets so no wire rests on the cooler or charge pipe. Use a written connector count rather than visual confidence in the cramped area.

Install the new filter and cap seal. Prefill the filter cavity only as permitted by the housing design, then torque the cap to 25 Nm. Refill oil to the service quantity and coolant with the approved mixture. A cold pressure-test method can expose a displaced cooler hose before the first heat cycle.

Fastener or setting	Documented value	Applicability gate
Oil-filter housing bolts	15 Nm	Documented EA113 configuration
Oil cooler bolts	15 Nm	Use a new seal and even passes
Oil-pressure switch	15 Nm	Verify switch design and sealing method
Oil-filter cap	25 Nm	New lubricated O-ring in correct groove

Fluids, adaptations, and first start

Crank and start while watching the oil-pressure warning. If it does not extinguish in the normal interval, shut down immediately; do not raise rpm to force pressure. Inspect the housing, pressure switch, cooler and filter cap with the splash shield still removed.

Run the specified coolant bleed or controlled warm-up. Maintain the expansion-tank level without opening a hot pressurized system. Confirm radiator-hose temperature progression and cabin heat, then install the splash shield only after both fluid circuits stay dry.

Prove the repair under the original condition

After the first heat cycle, shut down and inspect with a dry wipe around the four housing bolts, cooler seam, pressure switch and hose connections. Scan for throttle, MAP and mixture faults that point to a missed air-path connector. Confirm oil level by the correct procedure.

After a full cold soak, correct the coolant level once and repeat the dry inspection. Road-test, recheck the shield area and save the final scan. The result is proven only when oil pressure is normal, coolant stabilizes and neither housing seam releases fresh fluid.

Common ways this repair goes wrong

• Mistaking oil collected on the splash shield for proof of the housing seam
• Breaking the aged PCV hose without staging a replacement
• Mixing the oil and coolant drains
• Forgetting the pressure-switch connector until the housing is fully seated
• Cross-threading a blind housing bolt
• Installing the splash shield before the first hot leak check

A repair is not improved by clearing a code, adding sealant, tightening beyond specification or skipping a blocked step. When a checkpoint fails, return to the last verified state and correct the cause before more parts are installed.

Exact repair checklist

• VIN, engine/chassis code and installed component revision match the planned procedure.
• The failed component or interface was proven before disassembly; the before-state is saved.
• All seals, fluids, required new hardware and special tools are present before access is opened.
• Connectors, hoses, fastener lengths, routing and timing/alignment references are photographed and labeled.
• Open fuel, oil, coolant, intake or refrigerant interfaces are protected and every plug is counted.
• Replacement parts seat without force; every structural or sealing fastener starts by hand.
• Final torque, angle, sequence and ride-height/temperature conditions match current service data.
• All fluids, bleed routines, adaptations or calibrations required by the exact vehicle are complete.
• First start passes the listed stop rules; the repaired area is checked before trim or shields hide it.
• The original symptom is repeated hot and cold, the final scan is saved and the next-morning recheck passes.

Minimum record to retain

Retain the VIN, engine or chassis code, before-scan, symptom conditions, disassembly photos, connector labels, fastener map, service-data revision and every measured value. Record the exact fluid specification and quantity added, all adaptations or bleed routines completed, the first-start observations and a cold recheck. A later technician should be able to tell what was directly observed, what was replaced and which same-condition test proved the repair without relying on the invoice description.

• The oil cooler must move before the cramped four-bolt housing can be removed.
• Housing, cooler and pressure-switch values are 15 Nm on the documented configuration.
• The documented filter-cap torque is 25 Nm.
• Oil pressure and coolant level are both required closure checks.

This workflow is marked completed only when its stated repair and post-repair checks are represented. It does not certify an unseen vehicle, replace current service information or convert a different engine/chassis variant into the documented configuration.