2005 X5 4.4 E53 N625UXFB53515LV14016
205,000KM
Background: recently bought from marketplace, no maintenance history and multiple compounding issues.
Flat rate for misfire diagnostic and repair.
Customer will be given direction for low cost maintenance procedures moving forwards and the engine compression will be increased by way of safe cleaning with engine oil additive auto-rx.
Recorded screenshot for cylinder roughness in INPA.
(Before) - showing only 3 and 7 contributing to normal operation. Showing 1,2,4,5,6,8 as running incorrectly.
Recorded stored code for multiple cylinder misfires, and stored individual misfires on cylinder 1,2,4,5,6,8
Stored code for bad ignition coil 6 and 2.
Stored code for engine coolant temp sensor failed the plausibility test.
Sensor is a threaded type, located on the water pump.
Observed there's missing hold-down clips and screws for the ignition coils - customer is advised to buy replacement parts.
Remove all coils, plugs, perform compression test.
#8 Coil had a petrified piece of secondary insulator over top of spark plug ceramic blocking access for socket to remove it required extra work to remove plug (1 hour) this extra work is unusual and will be an extra charge. The spark plug tube was vacuumed out due to rubber pieces which fell down.
Inspection of spark plugs determined wrong type for vehicle was installed (N62 engines do well with single electrode, existing had 4 electrode design.)
Perform bench test on 8 existing ignition coils, and inspect existing spark plugs.
Three ignition coils did not produce any output.
Tested and compared existing spark plugs to new and gaps where too worn.
Sold four good tested used replacement coils
Sold 8 new spark plugs
Perform compression test (PSI) to confirm basic engine health.
Remove fuel pump fuse #47, 25A
1 175
2 100
3 190
4 175
5 175
6 175
7 175
8 75
Install 8 new NGK BKR6EQUP replacement spark plugs torque to spec of M14 - 30 nM.
Install 8 good tested ignition coils.
Upon first startup after new plugs/coils; record screenshot for cylinder roughness in INPA.
Engine is running more smoothly, but could use some more improvement.
Execute learn new variants in inpa
Execute ram_backup and steuern_vvt in tool32 to force relearn in vvt solenoids position and camshaft timing adaptation.
Command idle up to 2200 rpm to observe cylinder balance.
Cylinder 4 and 8 are at +1.3 and +2.64 of loss on roughness test.
Cylinder 8 has 75psi of compression - explaining less power contribution.
Cylinder 4 may have an under-performing fuel injector that can be improved with cleaner additive.
Engine health check determined timing chain is operating within its life span (camshaft adaptations are good)
End job by re-assembling parts taken off during work performed.
Recommended next steps for owner:
Order and install clips to hold spark plug coils. Without these clips, the coils will back out and misfire/break down shortly. Replacement part number for clip is BMW 11127546661
replacement part number for screw is BMW 11127521756. Requires four clips and four screws. These parts are only available at dealer, used or online.
Order and install coolant temperature sensor on the water pump.
Replace upper heater core coolant hose and clip due to rubbing on steering shaft.
Inspect rear subframe or engine mount bushings due to bang on high torque loading. Rear subframe bushing tool is available to rent if required.
Perform coolant system stress test at cold engine, added 25 lbs pressure, with engine running and observe for leaks. Age and condition of cooling system is critical.
Replace all fluids/filters: engine, transmission, differential, axles, coolant, brake, power steering
Engine oil cleaner additive auto-rx must be added for a clean cycle with 15W-40 diesel engine oil - buy a 20 litre pail. (Must NOT be synthetic).
Follow instructions https://auto-rx.com/seal-leaks-high-mileage-engines/
two oil changes must be performed properly to see a benefit of increased engine compression.
91 Octane minimum fuel must be used and Chevron Techron fuel injector cleaner must be used on a full tank. Customer to buy from amazon, they don't sell in stores: https://a.co/d/dJ3Nnwb
4X4 light is on - transfer case has a problem. Potentially in a safe mode that keeps in rear-only drive.
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