Cayenne S tows into the wind

It was a hell of a wind yesterday evening, but Charlie had to get to Canadian Tire Motorsport Park just east of Toronto to play with his BMW and work as a Porsche Club of Canada instructor for the weekend, so he set off at 6:00 from the farm towing the 20 X 8.5 enclosed trailer loaded with his car and equipment. I checked with him at 9:50. He had just arrived.

The load-levelling hitch evened the suspension out pretty well, but the problem was SW winds were so high they had closed the airports in Toronto, and the Hamilton Skyway Bridge shut down as well because of wind gusts over 75 mph. Headwinds were a minimum of 30 miles per hour, with gusts passing 50 mph.

The 2004 Cayenne S pulled the bulky trailer through it well, according to Charlie. I asked him about the fuel consumption.

28.5 L/100 km. Normal is in the low 12’s for mixed driving. That was a serious pull over a relatively flat road. He did say it was very windy.

UPDATE: 6 May, 2018

This evening Charlie told me that when towing the trailer into in that 60 mph headwind, there was no change in engine effort when going down hills. I insisted that he check the engine oil. No change in oil level from before the vigorous exercise.

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Senior moment

In the Costco parking lot this afternoon I found myself tightening the left front lug nuts on my Porsche Cayenne. Of course today had been the day I decided to put the summer tires on, so I had Ruby up on the hoist and the wheels switched before 9:00 a.m. Seems the studs were rustier than they looked, and I forgot the torque-wrench stage.

It was fortunate that I had had to back out of a trick parking space at the Rose and Crown (fish and chips to die for) and the studs alerted me to their looseness after the prolonged full-lock maneuver. What astonished me was how many turns it took to make the four loose studs tight again. One was still intact. The studs must have been working themselves loose while I was driving down the 401 at high speed. And there was no warning until I cranked the steering enough to allow the wheel to rattle a bit, fifty miles into the trip.

Initially it sounded like a rear brake spring loose, but over a mile of driving it became steadier and louder. I parked, loosed Bet into the store, and set about with the on-board tool kit.

The tire wrench works, and I couldn’t bend it with the limited brute force I could generate. Later the torque wrench set at 105 foot pounds only tightened one stud any more before clicking. But on the left front, four of those studs had required many turns with the emergency wrench.

Crisis ended, I headed for the lunch bar and a dish of chocolate ice cream. Then came my only inspired moment of the day. My wife habitually vanishes into Costco and I can’t find her until she is ready to come out. Instead, this time I texted: “Chocolate ice cream in dish with two spoons, at the tables.” Very soon thereafter Bet showed up, took a spoon, and helped herself to the bait. She knew I would eat it all, so she had temporarily abandoned her cart to protect my blood sugar. Kind, self-sacrificing woman.

Even kinder, she did not rail upon me for forgetting to tighten the lug nuts, and even offered not to tell Charlie. Oh well, if he reads this he’ll know, and resume clandestinely torquing the wheels on his Dad’s cars.

Do you have any idea how much that hose costs?

The sole casualty of my bumbling exploration of the area under Ruby’s manifold was the following little crankcase vent hose. Pelican Parts offers it for $183. USD, plus shipping, exchange, taxes and fees. All for a little crack.

The trouble was that there was no space for clamps.

One contributor suggested gluing a copper junction piece in, but one end needed a regular piece of copper pipe, so I modified it a bit, then cut the end off at an angle to accommodate a slight bend in the hose. The moderator of Rennlist.com warned me in no uncertain terms not to use any product with silicone in it or it would kill the O2 sensors on the engine.

JB Weld is apparently as good as its reputation. A mixture of limestone, steel filings, and epoxy, it works well in engines.

After a couple of hours to set, the repaired hose slid neatly into position. I left it for a day to finish its cure in a warm shop, then it worked fine.

Changing Ruby’s spark plugs, etc.

It seemed like an easy job now that I had the beauty covers off the engine, so I bought a set of the correct Bosch spark plugs and had at it. I even laid in a new 5/8″ spark plug socket with the rubber insert to help me pull the loosened plugs out of the long tubes which guide them down into the engine.

Yeah, right. The first plug wouldn’t stay on the wrench, so I recovered it with a magnet on the end of a cable/coil arrangement which allowed me to open a grappler down the tube and grab the loosened spark plug. When I installed the fresh plug, the rubber sleeve from the expensive spark plug socket stayed on it, now torqued into the cylinder head. There was nothing to do but remove plug and all, and from then on use the grappler for the handling of loose spark plugs.

My phone provided essential information: torque the plugs to 22 foot pounds.

As I removed the old ones, most looked to be in excellent condition, but #5 and #6 showed some carbon on them. It was time to do this job. #5, for reference, is the spark plug closest to the driver’s side headlight on a left-hand-drive model.

5 through 8 are very easy to change. 1 through 4 are more of a challenge.

After one removes the beauty panels which surround the engine on a Cayenne, the coils and spark plugs are covered by a pair of decorative plastic fingered things which clip and screw on. They significantly reduce injector noise and protect the wiring harness, so they are not just a frill. The only problem is that on the right side, one of the fingers slides through a complex engine mount, and another doesn’t have quite enough room to slide out from under an air pump at the rear of the engine. First use a 30 torx screwdriver to remove the screws holding the fingers down. You’ll need a tiny ratchet and the equivalent bit for a couple of tight spots, but this shouldn’t be difficult.

Needless to say, if you don’t have access to a set of triple-square male sockets, you can’t go any further. There’s this arm which reaches from the right fender well to the side of the engine. A bolt can be readily removed with a 16 mm socket at the head and a 12mm triple square thing on the other end. Then the fender connection can loosen with the same 16 mm socket and allow the torsion arm to fold out of the way. This becomes a routine operation if one is to spend any time under a Cayenne’s hood, but it’s a non-starter if one has misplaced the triple-square male socket set.

The air pump hanging over the back of the engine, one of two, is easily moved out of the way. Just remove three screws (torx #30) and let it flop loose. It’s not fragile. Unfortunately there is an aluminum frame which holds it. It has a machine screw down into the cylinder head, some sort of strange hex bolt, but an 8mm socket will work on it. Loosen that until the air pump mount can wiggle enough to let the finger out from underneath without shattering. Remember that Porsche plastics do not age well and are prone to failure when stressed. I found over several repetitions that if I removed the oil filler cap it allowed the fingers more room to wiggle without twisting. Stuff a clean rag into the open oil filler, of course.

Once you have removed the finger cover, you’ll discover that the coil for the #3 cylinder can’t come off unless you remove the rest of that engine mount. It is fastened to the right cylinder head with four hex bolts, 10 mm on top, and more of those strange green 8mm things below.

Once these obstructions are out of the way, it’s a simple job to remove the coils and change the plugs on the right side. The coils are freed with a 10 mm socket on a small ratchet to back out the the complex studs which one level up held the screws for the fingers. Once they are out of the way (Don’t lose any!) I found that the upholstery tool, a broad, angled screwdriver with a notch in the centre which comes with most screwdriver sets, is the ideal device to persuade well-established ignition coils out of their dens.

*Triple square is like a 12-point Allen wrench.

Once the plugs are in and torqued, it becomes a matter of re-installing the ignition coils. All of the old ones I had removed had 2″ vertical splits in the side that goes down the tube, but they worked well. I had new ones to install, so I cheerfully clipped them in, fastened everything back together, and fired Ruby up.

Ruby’s ignition missed quite badly, so I put the OBD II meter on. P0308, 301, 302. Ulp! Much fussing led to the conclusion that half of my brand new Chinese coils did not function. This led to an interesting afternoon of chase-the-ignition fault until at long last I had it nailed down to just P0308. With a prayer I replaced the new imported coil with the original, cracked coil which had come out of cylinder 8. Ruby fired up and purred.

I can’t emphasize enough how desperate a misfiring Cayenne V8 appears. My son says it has to do with the O2 sensors. If one detects a richer mixture because of a misfire, it leans out the entire bank of cylinders. So tic-tack-toe with old ignition coils and potentially defective new ones is a real challenge. But once it runs, it runs beautifully. It’s more like computer programming than auto mechanics.

Then it’s just a matter of putting everything back together and testing the car on the road. In my case this step occurred a few times before success. After enough repetitions the engine mount and air pump routines become familiar and strangely comforting.

And that’s how you change the spark plugs on a 2004 Cayenne S.

With the new plugs Ruby averages 12.1 litres per 100 km. That translates to a fuel consumption rate of 23.35 miles per Imperial gallon on 91 octane. That’s about what my Volvo 240’s used to do on regular.

UPDATE: 2 May, 2018. I notified the Amazon vendor that only half of the coils in the batch actually worked. He sent me another box of eight new coils in short order, so I get to try again.

UPDATE: 3 May, 2018 The vendor sent me eight new coils from another batch. They went in and perform flawlessly. I have become rather proud of my Porsche Cayenne tune-up skills as a result of all of the practice.

A final word on Porsche coolant pipes

After some correspondence with a contributor on Rennlist.com, I decide to satisfy myself that I can tell if a Cayenne has had its coolant plastic coolant pipes replaced with the aluminum upgrade by looking from outside. I take the scope and snake its camera into the back of Ruby’s engine compartment with only a vague idea of what evidence I am looking for, but convinced of the outcome because we have already lifted the manifold and looked at the array of aluminum below.

Eventually I tell myself I see a satisfying flash of aluminum casting just below the elaborate black plastic casting of the intake manifold. The next step is to take this methodology into the engine bay of my son Charlie’s nearly identical car to determine if it has also had the upgrade.

This proves daunting. There is an aluminum casting in the correct location, but things generally look different. After much fussing Charlie and I conclude that on Ruby the tech left out a black plastic component which sits above the pipes running toward the back of the engine. Anyway, the upshot of it is that the gray Cayenne has also had the coolant pipe upgrade, we think.

I find it hard to believe that my surgeon can replace heart valves with a variation on this scope. My hat is off to him. I can hardly find the back end of an engine with mine.

BTW: I have an unused coolant-pipes-kit in the shop with shipping and Canadian sales tax already paid, if anyone in Eastern Ontario would like to take it off my hands at a bargain price.

Coolant pipes diary: Day 2

NOTE: The passenger side is right, the driver’s side is left for the purposes of this article.

8:00 a.m. Restless and anxious to get at the project, but must wait for son to arrive. Make work. Build fire in auto shop. Brush the dog. Clean car mats.

Enough of this. I want to wrench. I decide to pull a spark plug to see their condition. The easiest access is the second cylinder from the front on the left. The coil has a 3″ split in the plastic tube, so I pick a new one out of the box and install it, but of course I can’t test it yet.

12:00 p.m. Charlie, Roz and Ada arrive.

1:00 p.m. We start in on Ruby. Charlie scopes and photographs, and we eventually agree there’s little point of further disassembly.

Charlie spends an hour trying to get the rear right screw into the fuel rail.

2:10 p.m. We partially remove the manifold to allow the installation of that damned screw. Now I understand why techs leave the fuel rails on the manifold, and remove the whole unit. The right rear screw is otherwise impossible.

Things go back together well. Charlie understands the strange packages with air running through them on the top of the engine. I content myself with putting on covers and clipping on injectors. Back go the fuel pump fuses, and Ruby fires up. There’s a slight miss which we decide to deal with after Easter Dinner.

4:45 p.m. The OBD reader shows P0202. That means the injector on cylinder 2 is misfiring. That’s the second one from the front. I quickly tear in to the coil I had replaced this morning, second from the front. No amount of abuse of the coil and the injector on what turns out to be cylinder #6 helps the problem.

Eventually I call up a diagram, realize I have been working on the wrong side of the car, take off the right air pump, loosen the air pump holder, remove the motor mount shaft and the notoriously fragile beauty cover which fingers in among these obstructions, only to discover an injector wiring connector which is loose under the fuel rail and an awkward clump of wiring. Ten minutes later it clicks into place. Ruby fires up smooth and powerful. I put the car back together, vowing to post a diagram of Ruby’s engine on the shop wall so I will always know where cylinder #2 is.

6:00 p.m. All better. Test drive is a quick, one mile sprint, and home.

Coolant pipes diary: Day 1

8:00 a.m. Fired up Ruby for what may be her last drive for a while. It might as well be an enjoyable road, the trail to Landsdowne, the International Bridge, and Wellesley Island in the middle of the St. Lawrence River where the local Kinek parcel depot flourishes in the back of the Wellesley Island Building Supply.

8:35 a.m. U.S. customs agent took my passport and asked: “Where are you headed today, Wellesley Building Supply or Watertown? You don’t look as though you’re going far.” He was right. I was back through Canadian Customs inside 15 minutes.

8:40 a.m. The parcel with the aluminum coolant pies kit was in, as promised. It felt so light that I opened the box on the spot to make sure it wasn’t empty. All there: aluminum is light, I guess.

10:30 a.m. Home. Removed Ruby’s engine beauty panels and a motor mount. At that point I ran out of the things I’d had practise at doing. Then I realized I wasn’t sure about how to disable the fuel pumps. Read for a while, becoming more confused by the manual.

1:00 p.m. Decided upon the two-fuse method explained by Harkness on RennTech.org. Pulled 13 and 14 and Ruby (Harkness identifies 14 and 15 as the pump fuses but his is a newer model) obligingly refused to start. Released a small bit of fuel from the end of the fuel rails.

Removed the spark plug covers. Then the air handling stuff at the front of the engine. The car is well built, though Porsche plastics are a chore.

3:00 p.m. So far, so good. Ruby’s apart. I’m stuck at the removal of the fuel rail. Don’t know how injectors detach or come out. Must read. Going pretty well. One screw lost from rear right fuel rail. As predicted by Harkness. Apparently those screws are never seen again. I also broke the predicted pvc hose made of desicated fortune cookie dough, also predicted by Harkness. Electrical tape works well on it. The rest is pretty sensible, so far.

4:00 p.m. Back at it after sandwich. Decided to fasten rails back onto the manifold. Lost a second screw in a careless attempt at left rear corner.
Backed out the manifold screws without difficulty. Compared to changing 7 A/C servos from the floor in front of the driver’s seat, this stuff is a cinch!

4:45 p.m. Shifted the manifold forward and up. Peeked underneath… Nothing but gleaming ALUMINUM under there! Hooked up the scope, probed carefully below. Starter and solenoid connections show no evidence of corrosion. A small amount of grass seems to have blown in recently as if it has had one summer only in a leafy area. No evidence of nests and the gleaming aluminum coolant pipes suggest Ruby has had a pampered life in garages in downtown Vancouver before taking over Charlie’s shop at the farm.

5:00. Notify family and associates of bathetic end to the coolant pipes project. General bemusement.

Shall enlist son Charlie on the cleaning and re-assembly. A few years ago he spent a winter’s weekends resealing a 968 engine, and he did a great job on it. He’ll definitely want to have input tomorrow, as the engine in his ’04 Cayenne S is next in line, and the parts are already in stock.