Porsche Cayman S catalyst and O2 DTCs.

I have a long story about catalyst efficiency DTCs on the 2006 Cayman S.  It starts back when I bought the car in 2014.  You can see that story here.  It had 60k miles on it when I bought it.  The car had a P0421 DTC which means "Warm Up Catalyst Efficiency Below Threshold (Bank 1)".  On this car that is the passengers side.  I installed an O2 bung on the muffler on that side and moved the downstream sensor there which generally eliminated that DTC, but I would occasionally get a DTC for the front sensor of that back stuck rich.  It would set that DTC randomly but not very often.

It did get annoying to have this DTC trip though, and I wanted to upgrade to better headers so I finally did in 2019.  I put the bank 1 downstream sensor back in the proper position when I installed the headers. The DTCs were finally gone for good, or so I thought.  I went to a track weekend in April just a month after installing the headers and I had no issues.  However, I went back to then same track in October and the car tripped the P0421 and P0431 ("Warm Up Catalyst Efficiency Below Threshold (Bank 2)") after idling for extended periods during warm-up.  Normally I just start the car and drive off but at the track the car sits and gets cold between sessions and I needed to get it fully warmed up before entering the track so I would idle it for much longer than normal.  It appeared the Fabspeed headers, in combination with this cold idle warm-up, was enough to fail the warm-up efficiency test. 

I suspect that these headers with the high-flow catalysts and larger, somewhat longer primary tubed are not as good at heating the catalyst, and that catalysts are enough less efficient that the test is below the threshold at times.  One of the known ways people get around this is by adding a spacer to the downstream O2 sensors.  This simulates catalyst oxygen storage to some degree and can help the test pass.  So, I installed some short straight extensions I bought through Amazon for cheap.

After installing these, I immediately got a DTC P2198 "O2 Sensor Signal Stuck Rich Bank 2 Sensor 1".  Since the car now has 87k miles on it, I replaced both the bank 2 O2 sensors but the P2198 remained.  I noticed the bank 2 upstream O2 sensor was loose when I went to replace it.  I checked and cleaned the MAF sensor, checked for vacuum leaks, re-torqued the headers and checked for exhaust leaks, and all was good.  Finally I removed the bank 2 downstream O2 extension and the P2198 went away and my O2 and catalyst monitors tested and passed (monitors were ready and no DTCs).  

Now, with an O2 extension in bank 1 but not in bank 2, I get these OBD test results (mode $06)

when the P0431 is pending.

Test report:
------------------
TID:$01 CID:$05
- Rich to Lean sensor threshold voltage(constant)
Min: 4,096
Test result value: 15,458
PASS
----
TID:$01 CID:$06
- Rich to Lean sensor threshold voltage(constant)
Min: 4,096
Test result value: 3,639
FAIL

I can't currently find the definitions of these but given that my pending DTC is P0431 I am presuming that CID $05 is bank 1 (which passed) and $06 is bank 2 (which failed and set the DTC pending.  You can see the large difference in test result values here.  The sensor without the extension is 89% of what it needs to be to pass whereas the other bank is 377%.  All other test results in the report passed.

I bought some shorter spacers and installed one in bank 2 only. 

I cleared DTCs and drove the car again, including cold start.  The P0431 sets pending again.  Here are the OBD test results this time:

Test report:

------------------

TID:$01 CID:$05

- Rich to Lean sensor threshold voltage(constant)

Min: 4,096

Test result value: 13,902

PASS

----

TID:$01 CID:$06

- Rich to Lean sensor threshold voltage(constant)

Min: 4,096

Test result value: 803

FAIL 

Strange how it is even worse with the spacer in bank 2.   Also interesting how the medium spacer works well in bank 1 but not in bank 2.  

It seems like my bank 2 catalyst is very weak, at least for the warm-up catalyst test.  

It is strange that I installed the headers March 2019.  I did not mature any DTCs for months of daily driving.  I did not check monitor readiness and did not check for pending DTCs however.  I did a PCA track weekend at Putnam that April and had no issues (that I recall anyway).  I went back to Putnam again October 2019 and that is when the DTCs started tripping pretty often.  Sometimes just one bank, other times both.  It would happen when I warmed up the car and would sit on the grid for long periods.  Since then I have had the P0421 and P0431 keep happening.  Now it is pretty consistent on bank 2..  

I drilled my original longer spacer out to 3/8".  I cleared the DTCs and drove the car.  After about 20 minutes of driving it finally tripped the P2198 again.  I cleared the DTCs, waited a few hours and drove the car again.  This time it completed all the monitors with no DTCs.  Here is my OBD Test results from that drive.

Test report:
------------------
TID:$01 CID:$05
- Rich to Lean sensor threshold voltage(constant)
Min: 4,096
Test result value: 10,503
PASS
----
TID:$01 CID:$06
- Rich to Lean sensor threshold voltage(constant)
Min: 4,096
Test result value: 6,404
PASS

The test result above looks great.  It just seems very inconsistent to get for bank 2.  Bank 1 is now solid and passes every time.  Bank 2 toggles between P0431, P2198, and an occasional pass.  

I took some pictures of Bank 2 catalyst.  Here is the view from the upstream side.

and here is the downstream side.

It looks good physically.  No cracks, chunks missing, melting, or soot buildup.  

I also checked it will then infrared thermometer.  I was in the garage so not much load on the engine.  After running (mostly idle) for a few minutes, it was about 400F both upstream and downstream.  I ran the engine at about 2000rpm for a minute and rechecked.  Now both were around 480F.  Not much temperature change across the catalyst in the garage.  This was the surface temperature of the pipe, not the actual catalyst temperature.  

I finally sent the header that kept failing back to Fabspeed to get the catalyst replaced.  Fabspeed was great to work with throughout this whole ordeal.  I installed the header back and have not had the DTCs ever since.  I also checked to confirm that the catalyst monitors did complete and pass.  I moved the car to my Las Vegas home where I needed a smog check to get registration and it passed the smog check as well.  

Garage parking indicator

 I shopped around for various parking assistance devices for tight garages, or any garage really.  There are various types but most require that you park a specific vehicle in a specific way to work.  For instance, the old tennis ball on a string really only works for the vehicle you set it up for, parked the direction you set it up for.  I wanted a system that would allow me to park any of my vehicles either direction while minimizing the distance to the garage door.  This way you maximize the space at the front of the garage.

Years ago in another garage I built a simple system using standard garage door sensors, some LEDs, and an old cell phone charger.  It works but this time I wanted something a bit better.  I searched again on the internet for a kit or system I could just buy and install but to my surprise there really is not one like the system I made.  

Here are the components I made the system using.  

• Yohii dual alarm beam detector $32.99
• 2 12VDC 2A power supplies $11.99 for 2-pack
• Weewooday 12V boat navigation LED strips $9.99 for 6-pack
• Terminal strips to simplify the wiring $9.99 for 10-pack
• 50' 18ga 5 conductor sprinkler system wire (obtained from local hardware store)
• Various screws and clips

I mounted the alarm sensors 18" high and the distance away from the door opening that I wanted.  This was about right for most bumpers or license brackets to interrupt the beams.  I wired one power supply to the sensor that does not have the alarm relay (less terminals).  The other power supply supplies the main sensor and the LEDs.  The sensor has a normally open (NO) and normally closed (NC) contact which is used to switch between the green and red LED strips.  

Main sensor

Terminal block above main sensor. Wire pair on right is power supply.  Wires going up go to the LED strips. Wires heading down connect to the main sensor.

Front LED strips (wall with garage doors)

Back LED strips

My system spans both doors as in this case there are on the same wall.  Other garages stagger the doors so you may need 2 systems.  I had the aim the sensors a bit into the garage to get the performance I wanted.  I had also planned to add some reed switches and a relay to disable the LEDs when the doors were both closed but after I got it working I decided it was not necessary. The extra wires were for that.  There are many variations to this approach.  I like not having anything to trip over on the floor, or things hanging in the garage.  I like that I can pull the vehicles in either direction, and move vehicles to different stalls and it still works.  

These doors do have sensors already to prevent closing the doors on things.  However, those don't indicate if you are parked in the right spot or not.  You can only guess and try to close the door.  I also found the sensors are mounted much too low to prevent closing the door in your car.  

Fixing Home Speaker

 I have a set of Polk Monitor series speakers from the late 1980's.  These are fantastic speakers in my opinion, even now.  However, in one of the speakers (each has 2 drivers) both drivers started crackling very bad.  Upon inspection I found the coils dragging on the magnets.  The drivers in the other speaker were fine.  You can hear the dragging when you press in on the passive bass radiator which pushes the drivers out.  

I looked into these drivers with are part number MW 6503 and have been discontinued.  There are copies available for $35 to $70 range each.

I experimented with pressing on the cone in various places to find a place where it would not drag.  It seemed to be an alignment issue.  Maybe they creped a bit over time? I decided I would try to align them back.  Nothing to lose here right?  Either I fix them or I needed to replace them anyway.  I took a piece of plywood and a vise and began carefully pinching an edge of the magnet where the dragging was gone.  This basically bends the driver frame a bit to realign the coil with the magnet.  To my amazement it actually worked.  Here is the after video.

This is tricky to get right.  The metal has significant spring back and you want to bend in small increments. You have to carefully get it to yield just a bit at a time and retest.  

Cayman S Water Pump

 I did a dumb thing but it turned out OK.  When I took the Cayman out of winter storage this spring and warmed it up for the first time in a while, I smelled coolant, although none leaked to the ground.  I have seen water pump seals do this before.  On most older cars the water pump has a simple bushing that runs in coolant so a small seep that quits is not necessarily a big deal.  My F250 would do this on severe cold weather but never had a pump failure.  However, the Cayman water pump is not like that.  It has a sealed roller bearing instead, which is far better and should last for life.  However, if you get coolant seeping through the bearing, the bearing will die pretty fast.  The grease will get washed out, the bearing will run dry, and fail.  Well, that is what happened to me.  I had noticed a growling noise from the engine when I started it that morning.  My first thought was far worse than a water pump.  I feared my IMS bearing was going out.  After recalling that I did see dry evidence of coolant from the water pump I sorta convinced myself it could just be some coolant on the belt, which can make all sorts of weird noises.  Honestly I was not that convinced, I was just lazy and in a hurry to meet with some friends.  

On my way back from breakfast where I was meeting with friends I heard a pop and immediately my steering assist was gone and the charging system warning came ON.  Right away I knew I had lost the belt.  I carefully drove the rest of the way home, accelerating moderately up to speed, shutting OFF the engine, and coasting between lights.  By the time I got home the coolant temp was a bit over 200F based on the gauge.  Still safe but I would not want to get it too much hotter.  With no belt, the coolant does not circulate.  You can't go very far like that.  In the video below you can hear the pop right at the beginning.

It is not real loud and I did have the stereo going.  I quickly turned OFF the AC and opened the windows too.  

Once I was home, I removed the panel behind the seats to expose the front of the engine where the belt and water pump are.  I saw the slack belt but upon further inspection I found the water pump shaft had completely sheared off and the pulley was just laying there.

Glad to see it was just a water pump, I quickly ordered parts through the local dealers online website. 

  

Mid-engine cars have a much trickier cooling system since the engine is in the middle, and the radiators are in the front fenders ahead of the wheels.  This makes it an air pocket nightmare.  A vacuum system is needed to pull a vacuum on the cooling system and suck the coolant in.  I found this one on Amazon for $39.99.

Having the engine behind the driver and not even visible without removing bolt-in panels and carpet sounds like jobs like this would be much harder.  However, it is not too bad really.  It takes about 15 minutes to remove the carpet section and both the top engine panel, and the front engine access panel. Once you have these panels off, access is pretty good for most things.  I will say charging the water pump on this car is far easier than most front-wheel-drive cars.  

I positioned the car on a ramp on the drivers side, and jacked up the passengers side as high as my jack stand would allow.  This positioned the coolant reservoir as high as possible relative to the car. I did this to keep the radiators and heater core full of coolant making it easier to ensure all the air was out when I was done.   

I started by clamping the radiator hose and one of the heater hoses.  

I loosened the hose connected to the water pump at the bottom and stuck an Allen wrench in it to allow the coolant to drain in a more controlled fashion.  In this position, and with the clamps in place, about 2 gallons of coolant drained into the pan I had to catch it.  I then removed the water pump.  It is basically just a set of small bolts.  The nice thing is the gasket is metal and does not stick to the block so it left a clean surface.  Here is a photo with the pump removed.

  When installing the new pump, make sure the longer bolts are in the correct holes, with the alignment dowels.  Here you can see the new and old pumps, both showing the alignment dowels.

Here is a photo with the new pump installed.

Before removing the hose clamps, I drew a vacuum on the cooling system and pulled in the coolant.  

I was able to pull in almost 2 gallons right away.  Remember to open the air bleed valve in the top of the reservoir to allow the air to escape the block while doing this.  I then released the clamps, installed the belt, and ran the engine.  With the engine running I could feel more air purging through the air bleed hose that connects from the oil cooler to the reservoir.  I added about a quart more coolant at this point. I ran the engine some more until I could feel the heater hose warm up, indicating I was getting coolant flow.  I ran the engine until the thermostat opened and I could feel the radiator hose at the radiator warm up, indicating flow to the radiators. I did all of this while the car was still raised.  I took it for a good road test, hitting 7,000rpm at times to create high coolant flow and purge any remaining air.  

The whole job took me about 3 hours.  Not too bad.  

Mercedes E350 4matic 150k miles

I wrote a review of this car when it hit 100k miles back in December of 2017.  It now has 150k miles and there is not much new to report.  I did upgrade the headlight bulbs to LED.

Here is the things I did to the car in the last 50k miles.

12/27/2017 105k mi drivers seat cover. This is a known issue on these cars. I bought the part and replaced it myself.

1/20/2018 107k mi drivers front tire road hazard warranty replacement

2/25/2018 109109mi blower motor. This had a very minor intermittent squeak. Very simple to replace.

3/13/2018 new windshield

6/17/2019 117,715mi front brake pads. This was the first pair of front pads!

7/8/2018 119,869mi spark plugs.

8/5/2018 121,555mi belt. Although it was still fine. It just seemed like a long time to go on a belt.

11/18/2018 129,401mi Thermostat and PCV cover. Both a simple job.

The car was hit in the back by an inattentive driver in December.

But Banishek and Will fixed it back up again.  Good as new.

This car drives pretty much the same as when we got it.  Runs and drives great, never uses oil, no issues really.

Kohler Engine Noise

I have a 2001 GT3000 Craftsman mower with a Kohler 23HP 2 cylinder engine.  I bought it used back in May 2009.  It has many hard long hours on it.  I had a 5 acre place I used it on for many years, and my lot now is over half an acre. 

I went to mow the lawn and heard a knocking sound.  I heard it while cranking as well as running.  Engine load made no difference so I figured it was not a main or rod bearing, or a piston issue.  It was an odd sound actually.  I listened with a stethoscope and narrowed it to the crankcase area, not the top end.

I removed the engine and as a drained the oil I could see the metal in it.

Once I took the engine apart, I checked the rotating assembly to find the source of the knock but it all looked good.  Everything was nice and tight still.  Piston skirts looked good too.  This was expected since the knock did not change with engine load.  I had to look deeper.  Finally I found where the crank had worn into the lower case (oil pan) which also serves at the lower thrust bearing.  Strange they have the crank go right against the end case aluminum to serve as the thrust bearing.  I could feel the crank end play was excessive too.  The knock was from the fact that the crank had worn so deeply into the end case that the crank throw was actually grinding into the oil pump gear and bolt.  

I measured the crank end play and found it to be 0.080".  That is ridiculous!  

You can see in the photo below how worn down the oil pan is on the thrust surface. This is supposed to be flat.

Notice the wear on the oil pump gear.

Here is what it should look like.

When I think back to the way it sounded it was not a pure knock.  It also had a grinding sound element to it.  Now it makes sense.  By the way, the photo above is a used part listed on eBay at the time I wrote this.  It had a buy it now for $45.  There were several others around the same price.  Far less than the over $200 for a new one.

Driving Exotics Racing in a Porsche GT3 RS

First person there in the morning

I drove a Ferrari 488 GTB at Speed Vegas last year.  This year I decided to try something totally different and drive the Mustang GT500 at Exotics Racing at the Las Vegas Motorplex.  I booked it the night before but when I got there, the car was in the shop so they asked me what other car I would like to drive instead.  I already had 2 at the top of my want list: The Porsche GT3 RS and the Porsche GT2 RS.  I was able to upgrade to the 991.1 GT3 RS for no additional cost so I went for it.  Exotics Racing does it a bit different than Speed Vegas.  The biggest difference is the 2 laps ride in a Macan to orient you with the track.  That is a nice touch.

The track

Satellite view of the track (Google Maps)

The track is 1.2 miles long with some small elevation changes and banking on turn 2.  The longest straight is still short (1800ft) but it is enough to have a great time and get a good feel of the car.  The mild elevation changes give you a feel of the cars balance under dynamic loading pretty well.  There are 2 turns that are well over 90 degrees.  This track was a bit easier to learn than Speed Vegas since all the corners are very unique.  It is very helpful to have an easy to learn track when you only get a few laps on it.  The drift car leaves a bunch of rubber on the track and much of it is off-line and that can throw you off as your eyes tend to follow it and not the true line.  The section of the track up near the building can get confusing too as the track appears to have been shifted but the old route still shows.  Here again the drift car makes a bit of a mess of it as it takes a different route out of the pits.

Comparing the tracks at Speed Vegas (1.5mi, 12 turns), Exotics Racing (1.2mi, 7 turns), and Dream Racing (1.2mi, 9 turns), Speed Vegas is the longest and you will hit the highest top speeds.  These are all short tracks.

The car

Instructor and I getting ready for the track

Out on the track

This is one of my favorite cars.  I am a big Porsche fan and the GT3 RS is the most engaging drivers car in the lineup.  I suspect the GT2 RS is even better in some ways (power obviously) but the GT3 RS just fits perfectly and does everything you want with no effort.  The sound from the high revving naturally aspirated flat 6 is one of the best engine sounds out there.  The engine response is very crisp too.  Being used to my Cayman S on tracks really helped as this car felt very familiar.  On this track we only shifted up on the main straight and back down in turn 2.  Of course I was plenty sloppy not being at all familiar with this track, or the car.  I never got the car to even squeal a tire.  The grip was fantastic with the Pilot Sport Cup 2 tires.  I looked at my ranking compared to other GT3 RS times at this track and I ranked 1500 out of about 3382, and 6451 out of  43165 for all cars.  I think the GT3 RS times included both 991.1. and 991.2 GT3 RS as they don't show them separately.

Full video of my run on YouTube

My time and rank on the day I ran 

You may recognize some of these folks at the top in the GT3 RS

This car is amazing.  Even with my sloppy 5 laps around this track I got a good feel for what this car may be capable of.  I was never at the limits of grip at any time.  I had plenty of room for more speed everywhere.  The 5 laps were over real fast.  In retrospect, more laps might be worth it.  I think I could easily trim 5 seconds a lap off my least bad time with just a few more laps (and a less nervous copilot).  He had me braking early and corning slow which I suppose makes sense until you get used to the track. I don't envy these instructors sitting in the passengers seat in a very fast car at speed on the track and no idea what kind of nut they have behind the wheel.  I highly recommend this, or Speed Vegas, next time you are in Las Vegas.  Next time I might try out Dream Racing so I can compare these three.