BMWCCA Visit and Tech Session

We had another annual tech session at our shop on Saturday, March 28, 2015.  (click on the picture to see larger versions)

Nice spring weather at Integrity First for our BMWCCA tech session

Nice spring weather at Integrity First for our BMWCCA tech session

a rare BMW M-Roadster with the S54 engine

a rare BMW M-Roadster with the S54 engine

First up was a quick lesson on fasteners, their materials, the advances BMW have made, and the importance of torque specs.

Tyler opens the show - Dan is not sold yet...

Tyler opens the show – Dan is not sold yet…

 

Inspecting fasteners

Inspecting fasteners

Our second topic was all about BMW’s cooling systems.  Including water pumps, system bleeding, electric water pumps, and why thermostats can set check engine / service engine soon codes in the engine computer (DME).

Cooling system goodies

Cooling system goodies

Inspecting the cooling system parts

Inspecting the cooling system parts

 

Damian doing what he does best:  over explaining (whilst waving around the cool air-lift bleeding tool)

Damian doing what he does best: over explaining
(whilst waving around the cool air-lift bleeding tool)

Our last topic focused on BMW’s V8 engines (did you know BMW used to make pushrod V8-engines? – don’t worry we didn’t either)…  We covered the strengths and weaknesses of the M62 series V8s including a dead 4.4L and a dead 4.6L

Don checking out timing gear on the M62

Don checking out timing gear on the M62

Checking out a stripped M62 - this one is a 4.6L

Checking out a stripped down M62 – this one is a 4.6L

An N62 engine in the X5

An N62 engine in the X5

A bad N62 problem:  excessive oil consumption due to bad valve stem seals

A bad N62 problem: excessive oil consumption due to bad valve stem seals

There were no shortage of cool BMWs visiting - check out this beautiful 6-series!

There were no shortage of cool BMWs visiting – check out this beautiful 6-series!

Dan brought the rear-end from his M3 for "show and tell"

Dan brought the rear-end from his M3 for “show and tell”

A special thank you to the Utah BMWCCA chapter and to Michael Bontoft for the photography.  See you next year!

Porsche Boxster S – Bad Engine Noises

Vehicle Details: 2005 Porsche Boxster S.  65,000 miles

Technician: Brad

Initial Condition:

  • Loud Engine Noise (sudden)
  • ALL Dash Warnings on
  • Towed in

Diagnostic Process:

Physically inspected engine – found broken-off water pump pulley:

smaller_JPG-3619

Boxster broken water pump pulley

Upon closer inspection it was clear this was NOT the vehicle’s original pump but it WAS a Porsche-OEM replacement.

Brad, as a Gold-Meister Porsche tech with over 15 years experience had never seen this before.

Boxster water pump shaft sheered-off

Boxster water pump shaft sheered-off

The pump’s impeller was NOT ceased.  Pump had been seeping from the bearing (see yellowish material on pump).

Conclusion:

Boxster new water pump installed

Boxster new water pump installed

This story ends well:  a new pump and belt and then a good road test demonstrated a successful repair.  No other cooling system or engine damage occurred.  This success was due to a diligent client that pulled over immediately and called in to the shop to arrange a tow-in.  AMAZING to see a problem like this but it goes to show anything can happen.

BMW Z3 with check engine light

Vehicle Details: 2000 BMW Z3 2.5L, Automatic Transmission, M54 Engine, 35465 Miles

Technician: Tyler

Initial Condition:

  • Check engine light on
  • Engine is running rough
  • **had recent oil change

Diagnostic Process:

Scanned vehicle and found the following faults In the Engine control module (DME):

  • P1522 control VANOS position inlet camshaft
  • P1520 control VANOS end position fault, exhaust camshaft.
  • Ran test plan for the VANOS control on both the intake and exhaust and discovered that the VANOS degree angles were not changing.
  • Removed oil filter cap and inspected oil filter, looked newer and was not plugged.
  • Removed the filter and found that the oil filter housing had been broken from someone doing an oil change.
Broken oil Filter Housing

Broken oil Filter Housing

  • Removed all of the remaining pieces of metal that were in the oil filter housing and replaced the broken oil filter housing unit.
  • Started the car and re-Ran VANOS tests and again found that The VANOS degree angles were not changing.
  • Removed the VANOS and disassembled and found that there was a piece of metal inside the unit that was causing the exhaust VANOS valve to hang up in its bore and not allow oil pressure to the VANOS gear/Timing actuator causing the angles not to change.
Vanos disassembled

Vanos disassembled

DSC_3612
Replaced the VANOS Unit with a rebuilt one and test drove the car and reran the VANOS tests and the car is performing well now.

Conclusion:

The client confessed to doing his own oil change and not being able to remove the oil filter cap.  As a result excessive force was used on the filler cap causing the internal metal flange to break.  Had he then replaced the oil filter stand before proceeding further the vanos would probably not have been damaged.  This is one of those tougher lessons to learn about not ignoring something that is broken.  End result was good:  the car runs well now.  Had more metal circulated through the lubrication system there could have been much more extensive engine damage.  Great work Tyler on figuring this one out!

 

Cadillac DTS Northstar with Constant Misfire

Vehicle details: 2007 Cadillac DTS 4/Automatic transmission/ Cadillac Northstar V8 engine 124,820 miles

Technician: Todd Hansen

Initial condition:

  • Stabilitrac light on
  • Loss of engine power
  • Rough running

Out of State Cadillac dealership attempted ABS repairs / no luck.  Recommended engine tear-down and partial (or possibly complete) engine rebuild.  Client came in looking for an alternative solution.

Diagnostic Process:

  • Monitored engine data with scanner and verified misfire on #6 cylinder as well #8 cylinder.
  • Removed #6 and #8 spark plugs, performed simple/basic compression test on those 2 cylinders, results:
    •  #6: 0 psi
    •  #8: 175 psi
  • Tested Cylinder #6 further:  leak-down test and wet cylinder compression test – still:  ZERO compression.  So far – dealership recommendations are correct:  The engine clearly has a mechanical problem.
  • Valves, or their ability to seal compression into a cylinder, usually fail for one of three reasons:  They overheat and their sealing surfaces pit – causing poor sealing (this is condition is called a BURNT valve).
  • We ruled this out because burnt valve conditions will cause low compression that will increase during a wet-cylinder test.
  • Knowing the client was looking for the possibility of an alternate solution we got out the borescope camera to get pictures of the inside of cylinder #6.
  • The borescope found one of the intake valves stuck open in cylinder #6 – creating a no-compression condition.
  • We now know:  the engine has a possible bent valve or broken valve spring.
  • We also know:  a BENT valve was not very likely because this problem was only in ONE cylinder.  Bent valves are caused by out-of-synch timing components and thus almost-always involve more than one.
  • Removed valve cover
  • Removed intake camshaft for that cylinder bank and confirmed that the valve was stuck open due to a broken valve spring:
Northstar broken valve spring.

Northstar broken valve spring.

  • Replaced the valve spring, valve seal and keepers – a job that can be done with the engine in-chassis and without engine disassembly if other tricks are used.
  • Re-assembled engine and retested:  Smooth running engine / no more misfire codes!

Conclusion:

Often dealerships will take the less risky road with repairs.  This is common with franchises since they are required to perform their services and their service recommendations within standards agreed upon that allowed them to become a franchised representative of the manufacturer.  Our alternate repair required buy-in from the vehicle owner and more risk since the possibility existed that time taken to diagnose and perform this alternate repair could have proven unsuccessful and thus resources would have been wasted.  The tipping point came from the use of the bore-scope – a tool that is simple in concept but very powerful.  End result:  better information lead to a better solution.  The client’s out-of-pocket expense was less than 25% of the dealership’s proposed repairs.

MINI Cooper S N14 Engine Misfire, Valve Timing Problems

Vehicle details:  2009 Mini Cooper S / N14 Engine / 66,xxx miles
6 speed manual transmission

TechnicianTyler Seawright (Master ASE Certified)

Initial condition:

  • check engine light on, hard starting condition and noisy engine.
  • Dealership diagnosed as valve timing problems:  Broken timing guides, bad VANOS pulley, and possible other repairs needed
  • Client came in looking for a second opinion

Diagnostic Process:

  • Verified with computer diagnostics:  misfire codes for all of the cylinders
  • Visual inspection of ignition components (spark plugs and coils) suggested they were ok
  • Tested basic engine datastream – found all parameter data with the engine off was correct, IE Coolant temp, Oil Temp, Battery voltage, Etc.
  • Monitored low side fuel pressure (the N14 is equipped with direct fuel injection system so it has 2 different fuel supply systems):  Low side fuel pressure system was good.
  • Attempted to start the vehicle and it started.
  • Ran running fuel pressure tests.  Fuel pressure within specs
  • When running the DME (engine computer) set a code “2B64 Intake manifold, unmetered air“.
  • Per MINI’s technical service bulletins, removed the valve cover to physically check the valve timing. With the camshaft alignment tools in
    place we found that the valve timing was correct.
  • Also inspected timing chains, guides, and tensioners:  all ok.
  • Further running tests found that the variable Valve timing( VANOS) degree measurements would not deviate from 36degrees.
  • Monitored the Duty Cycle command to the VANOS Solenoid actuator and noticed that the Duty Cycle was changing when being commanded from the DMEto change but the actual valve timing was not changing.
  • This lead us to a physical fault with the VANOS system that cannot truly be measure electrically by the DME.
    We removed the VANOS Solenoid and found that it was physically broken and was not able to supply engine oil to the VANOS gear and therefore would not change the valve timing.  (pictured below – broken solenoid in front / new (good) solenoid behind)

MINI_VariableValveTiming2 MINI_VariableValveTiming1

 

Conclusion:

This is a classic case of a physical inspection trumping what a diagnostic tree / computer diagnostic process suggests.  The dealership followed all MINI protocols and formal test procedures to conclude, consistently but incorrectly, that the problem was with the physical valve timing components.  Knowing that as a weak-spot in this engine design, MINI’s repair suggestions weren’t a bad thing for the vehicle but would not have fixed the client’s concerns.

In the end, we saved our client over $1300 of misdiagnosed repairs.  A big win!

Smart TIP:

This engine is not equipped with a oil level warning system to alert the driver that the engine oil is getting low. We Suggest that every other time you fill your car with gasoline, Check the engine oil.

BMW M62 engine failure

This failure could have been avoided:  the oil pickup tube was clogged from a previous repair.  The timing guides were starting to fail and thus were replaced / the shop didn’t sell the additional work of removing the oil pan to clean the pickup tube.  As a result pieces from the timing guides made their way to the pickup tube and restricted oil flow.  This lead to oil pressure loss and catastrophic failure of the main bearings.  Net Result?:  Whole engine replacement for this otherwise perfect X5.

Failed Emissions in Salt Lake County??

If you own a 1968 to 1995 vehicle registered in Salt Lake County you may find a nasty surprise next time you take your car in for an emissions test…

YES: the test has changed and YES for these cars it is (generally) HARDER to pass!

Cars in this age range have to pass an actual exhaust ‘sniff’ test. The machine at the emissions test station measures pollutants in the exhaust – the ones that Salt Lake County care about are: Hydrocarbons (measured in Parts per Million or PPM), NoX (nitric oxide), and Carbon Monoxide or CO (measured as a percentage). Your emissions report also contains your vehicle’s emissions of CO2 and O2 but these are not regulated.

Having to pass an exhaust sniff test is not new for these vehicles but what is different is how the test is run. Historically an exhaust test was run with your vehicle on a dynamometer (with the vehicle’s drive-wheels running on a treadmill device) to test your engine under load. The big change is that now the exhaust is tested without the dynamometer but at two engine running conditions: idle and 2500 RPMs. Unfortunately we’re seeing a trend of vehicles in this age range (1968 – 1995) that would pass the old test but cannot pass the new.

What’s the problem? We are finding cars that fail this new test are failing the idle test. Typically they are showing results of a rich running condition (HCs that are too high coupled with high CO readings). These older cars were built with simpler engine management systems (if any at all!) and typically to get the car to idle well without stumbling/stalling at idle or hesitating when accelerated from idle the engine was tuned to run a little on the rich side to improve how it ran. Today’s engines and their engine management systems can react quicker to a change at idle and thus can be run more lean at idle. So this compromise of running a little rich to tame the engine at idle is causing the vehicle to fail the idle emissions test.

What can you do about it? This is the hard part: if your car meets this new emissions-failing profile you may have a lot of work (and expense) in front of you. The only thing you can do is to get the idle-condition running cleaner. This will require the very best from your car: perfect fuel delivery (clean injectors, perfect fuel pressure management, optimal operating temps, etc), a good condition ignition system, and a healthy mechanical condition of your engine. Be prepared to work with a specialty shop (like Integrity First Automotive) that can tune and tweak your car to its optimal emissions performance. Be prepared that this will require your maintenance to be current, and all of your fuel system to be working correctly. If this can’t get your emissions in range consider thinking outside the box: you may need to improve your chances by improving your vehicle’s engine management. ALWAYS follow the rules or your could be stiffly fined for ‘tampering’ but, where legal, there are a lot of modern solutions to add or improve the fuel injection system on your car.

Be aware that this can be a long and costly process. If your vehicle isn’t worth much to you it may be time to consider replacing it. We predict this new emissions test will result in less of these 1968-1995 vehicles on the road in Salt Lake County. Which, ultimately, is probably the goal.