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He didn't specify Techron fuel injector cleaner... just injector cleaner and every other one lists alcohol as the ingredient. Expensive alcohol that doesn't do anything more than the alcohol that is already in what passes for gasoline today (I hate the stuff and wish they'd get rid of the mandated alcohol since it really doesn't accomplish anything beneficial except cause cars to get 3%-5% less miles per gallon because alcohol has less energy per volume than gasoline. Since the government mandated gasoline additives in all gas regardless of where it is sold, there is pretty much NO NEED for fuel injector cleaner. Coked-up direct injection engine valves can be cleaned with cleaners like CRC valve cleaner that is put in the intake path with the air so it contacts the valves directly. Today's coked-up valves are just about impossible to clean with anything you put in the fuel tank. And this "top tier" fuel thing is mostly a joke. If you sit at a refinery and watch what happens, where the incoming empty tankers fill up, it doesn't matter what brand or name is on the refinery, trucks of almost all brands pull up and get their tanks filled with the same gas that goes into "generic" tanker trucks that deliver fuel to non-name-brand gas stations. I've been in a Chevron refinery near here (related to my job before I retired) and watched this happen 25 times over 4 hours or so. More Chevron tankers than other brands came to fill up, but there were Texaco trucks, Exxon trucks, generic trucks, and Arco trucks there, all filling up from the same distribution facility at the refinery. No-brand or regional-brand gas companies can't afford to build and run an entire refinery just to produce "sub standard" gas for their stations. They get their gas from any refinery that will sell it to them for whatever is the best price that day. This only makes sense... if you have a Texaco gas station that is 1000 miles from the nearest Texaco refinery or distribution facility (always located at a pipeline very close to the distribution facility), nobody is transporting Texaco fuel to that Texaco gas station... they will get fuel from the closest distribution facility or refinery. It benefits oil companies to advertise their fuel as being something special compared to other brands, but the differences either don't exist at all or are on the same level as a putting 1 or 2 drops of something in your pint of beer. Also... modern electronic direct fuel injection is high pressure on-off-on-off system and at the high pressures, anything that starts building up in a nozzle gets literally blasted out of the injector nozzle. It's pretty difficult to get a bad spray pattern in a modern injector until it gets worn enough that it no longer meters the proper amount of fuel when it is actuated. The old continuous injection mechanical systems (K-Jetronic, etc.) were a PITA for keeping the injectors clean enough to make a nice cone-shaped spray pattern... no alcohold in the fuel back in the 1970s and into the 1980s to help keep injectors clean so those pre-sequential/electronic fuel injection systems did benefit from alcohol-based fuel injector cleaner, though you would need a LOT more of it in the gas tank than comes in the 16 ounce bottle... in a 15 gallon tank, you'd want 1.5 gallons of alcohol to really do a good cleaning job... 12 of the 16 ounce bottles.
We're wandering seriously OT here - but I had a friend who worked in the big EXXON refinery in NJ - and yes - different brand trucks pull up - but the gas pumped into them has the additive package added as it's pumped into them, so not all gas is the same leaving the refinery.
Even with direct injection Techron can be a benefit. Carbon buildup on the piston crown still happens, and Techron can clean that off quite nicely.
The downstream-flush for the back of the intake valves on DFI - as far as I'm concerned - the jury is still out on if and how well that works. What does work is physical removal of the carbon (and there are lots of websites addressing that..) Mine were done when my heads were rebuilt, and it did make the engine idle a bit smoother. Not much else changed, but with a turbo pushing air into the cylinder I wouldn't expect it to.
In response to the discussions about the injection cleaner, I used STP Injector Cleaner. Didn't expect any miracles, but reading some reviews online - it seems to have a noticeable effect in certain cases.
The past couple of mornings the car has not been starting as easy as it normally does, checked the battery and it seems fine. Voltage seems stable at around 13,5v. Decided to go ahead and replace the spark plugs, according to the previous owner they had been swapped recently but then again, he claimed the same thing about the coils so...
Managed to find 8 Bosch OEM spark plugs for just $40, which definitely feels like a bargain. Hopefully, the plugs will arrive before the weekend so I can try to swap them then. Anyone with experience of replacing spark plugs here? If so, should I go pick up a torque wrench just to be safe or is it OK to tighten the plugs with just moderate amount of force?
Buy the torque wrench. And do NOT use ant seize (or anything else) on the threads. The torque wrench will hopefully prevent you from pulling the threads out of the head.
Not sure what that device is, but looks like it could be part of the security system. Interior motion detector (white-ish panel) and an audible alarm... crosshatch thing/grille. But might also be the audible tone when you get alert messages from the instrument panel... somebody is likely to recognize this if it is Porsche equipment. If there's any labeling on the back, you could google the part number if it is molded into the back and see what comes up. Part numbers usually start with 3 numbers representing the first Porsche model to use the part so could be 911, or 955 or 958, etc. As for spark plugs... use extreme care when removing plugs as well as when installing. Use a real spark plug socket to prevent strain on the insulator that can snap them ("real" spark plug sockets usually have a high density foam inside the socket and the insulator fits snugly into a hole in that foam. Also helps keep the plug in the socket when removing and installing plugs. You can strip threads in the head (aluminum heads) if the threads on the plug and the threads in the head have started "becoming one" due to galvanic corrosion (from dissimilar metals being in contact with each other over time with the assistance of high temperatures and water or salt water (worse). Aluminum expands more than steel with temperature. That means removing stubborn plugs will be easiest with the cylinder head warm... BUT if the cylinder head is warm when you install the new plugs, you have a better chance of pulling threads out of the head. So warm cylinder head can help with plug removal, but heads should be as cool/cold as possible when INSTALLING replacement plugs. If a plug seems "sticky" coming out, turn it 1/4 turn counterclockwise, then tighten the plug lightly, then back out the plug 1/2 turn, then back in a 1/4 turn, then out 1/4 turn, etc. until plug loosens. It may never get loose though, and you may have to use this procedure for the entire removal process... much safer than turning the plug out to remove and just apply all the pressure in the world to get it out. Something that can get overlooked: (I've never seen the plug locations in a Cayenne V-8, but assume this applies to some extent), it's a very good idea to blow around the base of spark plug with compressed air before starting to remove the spark plug. There can be grit (sand, tiny pieces of stone) resting on anything remotely like a "top" surface of a plug hole. The grit can fall into the cylinder if disturbed by touching it with the replacement plug when installing plugs. When removing plugs, I would suggest a 3/8-inch rachet and extension since using 1/2-inch tools can encourage too much torque on removal or install. AND, when inserting the new plugs, use the spark plug socket on an extension with no ratchet or breaker bar so you have to turn the small diameter of the extension to screw the plugs into the head. This will help you get the threads started without cross-threading the spark plug. Screw the plug in as far as you can before putting a ratchet on the extension to finish tightening (actually, torque wrench is best because the steel plug and aluminum head can have problems if the plugs are too loose OR too tight. Check recommendded torque for plugs in your engine and make sure the torque wrench you get has that value somewhere in the middle of it's range rather than being at the low end or high end of the working range for that torque wrench. If you feel any resistance with the finger-tightening, don't force it, back it out and try again. Plugs are supposed to have a coating on the threads that keeps the threads from seizing in aluminum cylinder heads... that coating isn't as effective as anti-seize. There is a lot of controversy over whether anti-seize on spark plug threads is good or not. There are 3 kinds of anti-seize I've heard of. Each has a different metal powder in the antiseize "grease"... aluminum, nickel, or copper. You'd think high-temp aluminum anti-seize would be pretty safe, but there still seems to be a lot of controversy around it...POSSIBLY because people use anti-seize so inconsistently... some slop it on leaving WAY too much. Others put a little dab on a finger and wipe it carefully on the threads making sure not to get it too close to the tip of the plug. Seems like the latter application method would be pretty darn safe... but the controversy still rages (much like oil discussions). One last note... I've seen people snap the insulator on a spark plug using a spark plug socket with the rubber insert... it seems to happen if they aren't careful about keeping the wrench aligned with the axis of the spark plug... when they tip the wrench enough, the foam will let the socket tilt and put uneven pressure on the insulator. So the rubber spark plug sockets aren't 100% fool-proof, you still have to pay attention.
Hi again all, yesterday I replaced my spark plugs. Thanks a lot for all your tips and input Scoot!
The old plugs actually came loose with little force I'm happy to say. However, the old plugs were a different spec than the new ones.
Before ordering I had, of course, both double and tripled checked various online dealers, all said to go with the plugs I ended up buying (26,5mm). But pulling out a shorter plug wasn't exactly a welcome surprise. I Googled and searched for hours to find any explanation for using these shorter plugs. According to Bosch, the short ones (19mm) are actually for the pre-facelift Turbo and Turbo S Cayennes. So my guess is that some workshop cut some very serious corners and installed whatever Cayenne spark plugs they had in stock.
Anyway, I finally decided to put in the new plugs with comforting results. I do believe the car runs a bit smoother and possibly a slight performance boost.
But, and it seems there is always a but with this Cayenne, it didn't start as easy as it should this morning. It also ran a bit rough the first 10-20 secs. I have received tips that a poor battery can cause these cars to behave badly in a lot of ways, so I try to keep my eyes on the voltage with a multimeter. As of this morning, it showed 12,6 volts before starting (had the charger plugged in during the night). What voltage should I expect from a fully charged battery in my Cayenne? Results I found online points to around 13,5volts rather than my 12,6...
If the original battery still is the one installed in the car I imagine it's definitely time to get it replaced since it's 9 years old...
Wellllllll... isn't THAT a special surprise! You just can't anticipate weird stuff like that. That would pull the spark that much farther away from the fuel charge, so it's not surprising you think the engine runs better with the new plugs. I'm sure it DOES run better. 9 years IS an old battery. 8 years should be pretty typical for an area without severe cold or hot weather. But 9 years in Sweden is a miracle! When you replace the battery, do not use an H8 battery... every battery replacement chart seems to say H8 battery for 4.8L Cayennes but they are all wrong. The correct battery size is H9. The H9 battery is about 5 cm longer than an H8 battery. You need the extra length to fit under the left front corner bracket that holds the battery secure. The H9 battery also will have more reserve power than the H8 battery, and that's always a good thing for a vehicle like the 957 which has a lot of electrical load. And an AGM battery is worth the modest extra cost over the common "wet" battery that has liquid acid inside. AGM batterys have an acid gel held in a mass by fiberglass fabric. There is no liquid an AGM battery. You can find some good videos on YouTube that show you exactly how to access the battery to replace it. You don't need any backup power connected when you remove the battery... if you disconnect the battery and everything loses power, when you connect the new battery, you don't get any alarms or need a code to activate the stereo... none of that happens. Some of your settings to the dashboard display may change back to default settings, but that's all that I needed to set back to my preferences. Radio memory was saved. But there's certainly no harm in connecting a power source while disconnecting the battery. When my battery was low, I would get random "Check Brake Lights" or "sidelights" or "headlights" warnings when there was nothing wrong. And when the battery was really low (would still crank and start the engine though) the motorized rear hatch would not work properly. By the way, my mother's side of the family came to the US from Sweden around 1860 and lived in northeast Ohio where much of that family still lives. My wife and I hope to visit Sweden, perhaps during our next trip to Europe... the last time we were in Europe (Britain actually, I know the mixed feelings about whether Britain is part of Europe or not part of Europe (geographically... the political/economic thing is a different matter!) was around 1995 so we are overdue for another trip.
From what I understand this is the OEM battery, can't really find any size measurment like "H8" or "H9" though. I'm planning to drive this car for another six months or so (dreaming about a Cayman S for next spring) so not really sure that a AGM battery is a worthwhile investment?
Cool that you have roots in Sweden, if I'm not mistaken, close to a million Swedes left during the 1800s to go live in the land of the free and home of the brave. If you do take a trip here, I would definitely recomend the summer months - they are actually in my opinoin just about perfect. Not too varm and not too cold, you can expect around 70-80°F. Side note, Gas prices are somewhat of a joke, I pay almost $6 per US gallon.
Your HPFP might be shot. Typical symptoms are rough ideal at startup and lack of power.
So yet another component that may need to be replaced... Not exactly what I would like to hear at this point hehe, but thanks for your input. I don't think I'm experiencing any lack of power, but of course hard to say if you're getting like 350 or 385hp..
Sorry to say, but you bought a complex 10 year old car with 111k miles. Previous owners tend to put cars up for sale at mileages like this when they notice a lot of subtle things going wrong. They do not want to diagnose or deal with the multiple often intermittent issues, so part of the unwritten discounted price is made up for with headaches.
Do you have any service records for the car? That is the first place to start looking.
There are many threads on here to diagnose fuel pumps, you could also be dealing with a small vacuum leak.
A couple years ago I heard about cam timing sensors for the variable cam timing. According to another forum the cam timing sensors get very dirty and report incorrect data to the computer. The resolution proposed was to do an oil change, using a good engine flush and replace oil with OEM Mobil 1 0-40 and new filter. (I have to add that this does make sense because if the variable timing is just slightly off the vehicle will vibrate and of course up here to be off timing.) I have an 06 Cayenne S and have been successful with this resolution twice. The vibration and misfiring/idle problems were completely resolved after about a hundred miles of driving. The vehicle has no issues for about a year or so until the oil gets dirty again at about 7 to 8000 Miles. The oil advertises that it can be used up to 10,000 miles and I now question this, and whether or not it has been the cause of the issue to begin with. I have never gone 10000 miles and usually change the oil between 3 and 5000 miles but have let it go as far as 7 or so in the past.
A couple years ago I heard about cam timing sensors for the variable cam timing. According to another forum the cam timing sensors get very dirty and report incorrect data to the computer. The resolution proposed was to do an oil change, using a good engine flush and replace oil with OEM Mobil 1 0-40 and new filter. (I have to add that this does make sense because if the variable timing is just slightly off the vehicle will vibrate and of course up here to be off timing.) I have an 06 Cayenne S and have been successful with this resolution twice. The vibration and misfiring/idle problems were completely resolved after about a hundred miles of driving. The vehicle has no issues for about a year or so until the oil gets dirty again at about 7 to 8000 Miles. The oil advertises that it can be used up to 10,000 miles and I now question this, and whether or not it has been the cause of the issue to begin with. I have never gone 10000 miles and usually change the oil between 3 and 5000 miles but have let it go as far as 7 or so in the past.
Hi, welcome to the forum...
HINT: We can talk more intelligently if we know your year/engine/model of Cayenne. They are a lot different.
Don't believe everything you hear from that other forum. There is no reason for the timing sensors to get "very dirty" - they are a hall-effect sensor - and that means they either send a signal at the right time or they never send the signal. If signals go missing you CEL will light right up.
More likely what's happening is the oil-solenoid that controls oil pressure on the cam timing adjusters (AKA VarioCam) is either getting gunked up, or yours is one of the years where Porsche put a screen in the head to filter out chunks of crap before they could get to the cam timing adjuster - and your screens are gunked up.
Fix is to clean the whole thing, this requires valve-cover removal and some disassembly - depending on which engine we're talking about. Before I did that sort of thing, I'd check the expected valve timing and the actual valve timing - something very simple to do with a tool like iCarScan or a Durametric (or a dealers PIWIS.)
Thank you for responding. The c e l light is on and performance is awful. I've not heard about the screen issue being plugged up? I have a 2006 Cayenne S v8 4.5
So you don't think the issue is the cam sensors?
Last edited by Daren Dozier; 04-27-2020 at 01:33 AM.
Reason: Add photo
07-29-2017, 12:26 AM
