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KPV

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Everything posted by KPV

  1. Hahnmgh63, Thank you for your input. I am picking up the car today from the dealer. After I get it, my hope is to do a compression test and also look inside the cylinder with my boroscope. This brings me to several questions about getting the best results when looking into the cylinder.... My goal is to look at three things, the top of the piston, the cylinder walls and, of course, the valves. To do this I will use it with and without the the mirror attachment. In order to see the valves, does anyone have a a diagram of where the valves are in the head? When I insert the boroscope with the mirror, especially since #4 is a little hard to get to at the firewall, I would like to see a diagram as to where the valves are. In other words, at 12 o'clock, 3 o'clock, 6 o'clock or 9 o'clock. That way I will know the right clocking of the mirror to see what I need to see. In order to see the top of piston, cylinder walls and valves, it makes sense to have the piston at bottom dead center (BDC). Is there a way to accomplish this other than trial and error? Thanks in advance for contributions.
  2. As I was doing my internet search for additional knowledge on this malady, I came across this... http://www.6speedonline.com/forums/cayenne/275907-help-need-cayenne-turbo-engine-05-a.html Several people say that the coating on the pistons comes off and wreaks havoc on the aluminum cylinder bore. This causes low compression. The thread also has two videos in it. They show removal of the engine in the "conventional" way up and out through the front.... http://m.youtube.com/watch?v=ceCmEbGiSq4 Is coating wear a known issue for these engines? I also found this thread about scored cylinders being a somewhat prominent problem... http://forums.rennlist.com/rennforums/porsche-cayenne-forum/567200-cayenne-engine-replacement.html
  3. Hi Guys, Thanks for the comments, feedback and suggestions. Before I go on, I will say that I am always suspicious of the diagnoses and suggestions of any dealer. I have known this service tech for probably 10 years. He used to be the service manager at a different dealership before moving to this one. The previous dealer had a big shakeup of staff and he and the head mechanic both moved on. I have always valued their candor and professionalism. That said, I am still always questioning everything at all times. Let me address your comments as best as I can at this point... RacerX: As for the compression test, I agree, it sounds very low. I spoke with another friend of mine in the indy business, albeit not Porsches, and he asked whether they did a dry and/or wet test. I wasn't sure what that meant and he explained that dry was with the car as-is and wet was after squirting oil in the spark plug hole, to presumably provide a better compression ring seal. Performing these two tests would yield results that show whether the compression rings are suspect (if the wet test jumps up in value) or it the compression loss is through the head (valves). It sounded like a great idea and I agreed with his mindset. This came about after I spoke with the dealer, but I will ask this question on Monday morning. As for the cost of engine removal, I totally agree that the cost was excessively high. I can't recall their labor rate, but at $120/hour, the $5,000 works out to 42 hours to remove, and possibly reinstall the engine. I will question this on Monday too, more for my own edification and curiosity than anything else. Regarding your second post comments, remember this is a $100k+ car. I am not, in any way, shape or form, considering a new motor. There are too many other 100k mile systems on the car that could be costly failures in the near future. I would rather move to a new vehicle than start dealing with a new engine (either new or reconditioned) in this car. I really don't want to throw more money at a bad situation, if it is something like the head, valves and/or potentially the rings. If it was something easier, simpler and cheaper overall, I would think about investing in the repair to get some additional mileage out of the car. There is a blurry line of worthwhile-ness that I am reasoning out. RFM: Regarding the oil vs. fuel, I smelled the old #4 plug. It was out of the vehicle for 1 1/2 days, but smelled like gasoline, not oil. I was told the new plug, which I have not seen since I installed it, was wet and the wetness was fuel. This is strictly what I was told by the dealer after they pulled the plug and inspected it. Your information about the DME shutting down the #4 fuel is interesting and that sounds like an expected Porsche failsafe design. But, that does not explain the low compression. In your last sentence, you say that the plug is dry after removal from a warm engine after a drive. The plug is wet, as was told to me by the dealer and smelled of fuel. These comments and my own reasoning has made me raise a new question... Could I have a leaking injector? Follow my logic here....If the injector is leaking, the air/fuel mixture would be very rich. The excess fuel could wash the cylinder bore and reduce the oil film lubrication. This would create a weak compression seal. This would produce low compression. Low compression would not allow the A/F mixture to compress enough, thereby reducing its volumetric efficiency. The end result is a less powerful burn of the A/F mixture. This would explain the rough idle, since the #4 cylinder is just getting by without adding much power to the overall combined effect of the other 7 cylinders. This would also explain the lower compression due to cylinder wash and reduction of oil film sealing. Can anyone address the validity of this idea?
  4. Loren, Thank you for the information. So, two questions... Do you have any thoughts on the idea of pulling the #4 injector wire to avoid washing cylinder bore with fuel in order to drive it to his location? Can the valve train cover be pulled with the engine in place? Thanks, Ken
  5. I actually just pulled out my scope and it does have a mirror attachment!
  6. Loren, I spoke to the dealer a short time ago and the answer to the "wet" question is fuel, not oil. This agrees with the old plug which I smelled and reported on last night. I am into the dealer for $300 at this point to pull the codes and the plug and perform the compression test. The car is buttoned up and ready for pickup. I talked with the DEALER further and following is a recap of the important points of our discussion... He listened in the area of #4 cylinder while the car was running and also took it for a drive. He does not hear, nor does he believe, it is a head gasket leak. No Pfft, pfft, sounds or anything like it. So, he feels the head gasket is not the cause. I asked him about his choice of words during our previous conversation wherein he said you may need a new engine. I explained how I reasoned it out, being fuel and thus relating to a problem in the head, and thus suggested a valve job. He response was that regardless, the engine and transmission needed to be removed. It would need to be removed to pull the head and it would need to be removed in order to put a new engine in. He quoted $5000 for just pulling the engine and transmission. I am told it drops out the bottom similar to the 911. His/their reasoning is that a new engine can be warranteed and it relieves the liability of just repairing the head/heads (presumably you would do both if you are that far with a complete engine pull). If you just deal with the heads, there could be issues associated with the gas injected into cylinder #4 running down the bore and affecting the lubrication of the rings in the bore. Seems to make sense. It is dependent on the length of time the issue was present. I would expect to see a dilution of the engine oil. I asked for a quote on the engine (more out of curiosity than anything) and it was $20-something. When I heard $20.., my ears closed and I didn't hear the end of his sentence. So, $21k, or $28k, it is largely irrelevant. This is where I left it with them. I am supposed to get the car tomorrow. I have also been speaking to a local INDEPENDENT that knows his stuff and I know through a friend. He has been helpful with knowledge and insight. His comments are: Recommended a leak down test of cylinder #4 at its TDC to see what was causing the compression loss. Listen at oil cap, at exhaust and at intake to isolate the loss. Sounds like sound advice. He seems to think it is a burnt valve, allowing compression to leak by. He also mentioned the possibility of a weak valve spring and/or sticky valve, again causing the loss. He has the Snap-on scope with the mirror and can look at the valves that way. So, with mileage like this, and a residual value of $15-$20k at most, one has to question whether to cut losses and sell the car with the problem (disclosing the knowledge of course) or invest in it with the intent to hold onto it for awhile. Very difficult decisions, especially considering the ambiguity of not knowing what the actual problem is!! One thought is to throw a little more diagnostic money at this with the INDEPENDENT so that a true educated decision can be made. If I were to do that, the big question is whether to drive it to him (80-100 miles) or have it flat-bedded. Will driving it (like a granny) do any further damage? Does it make sense to detach the wire to the #4 fuel injector to drive it there so that fuel cannot wash down the cylinder bore? Roy, That is a great idea. I know it is probably commonplace for something like this, but I never thought of that. I actually have Milwaukee's version of the boroscope (see below). It can only view straight ahead, as far as I know. But I am about to look and see if there are any mirror accessories available for it. As always guys, I very much appreciate all of your help. Thanks!
  7. Loren, I will ask that specific question in the am and report back. I have to be honest though, the low compression has me very concerned. Thanks, Ken
  8. Hi Loren, First off, thank you for responding. It is greatly appreciated. Also, please note the photos are of the old plugs and old coils. That said.... The plugs and coils have been sitting there for 1 1/2 days, but with a good sniff I can detect a faint gas smell on #4 (That is #4, right?) So.... My mind says, ok, the old coil or plug wasn't sparking correctly, or at all, and the injected gas didn't burn thus leaving the gas residue on the plug. Seems to make sense based on my reasoning. So, this raises several questions: Why would the new plugs and coils still show a misfire in #4? What would explain the low compression in #4? Why would the new plug and coil still be wet? This was told to me today by the dealer. Thanks in advance for your continued help. Ken
  9. Here is a little better photo of the spark plug electrodes.... Orientation is the same as the first photo.
  10. Hello All, So, a brief history... I have a 2005 Cayenne Turbo. I bought it used (coming off of a lease) with 17,000 miles. I now have 105,000 miles on it. Several days ago, it started to exhibit a rough idle. Additionally, especially at low RPM's (2k and below) it would exhibit rough acceleration. About 2k RPM's it would smooth out a bit, but not quite right. The next day, the CEL came on. I did some research and found the many threads on here, and elsewhere, about the coil packs. I bought 8 new coil packs (suffix=20) and 8 new NGK BKR-6EIX spark plugs. I checked/gapped the plugs to 0.032". I installed the new plugs and the new coil packs. I really thought I had the problem solved. When I started the car, the rough idle was a little less, but remained. When I took a drive, the rough acceleration was less but remained. I decided to bring the car to the dealer to have them read the codes. They called at the end of the day today and told me that cylinder 4 was showing a misfire. I was not on the phone long enough to get the actual codes. But, I will be speaking with them in the morning and will get the codes. They also told me that they pulled the cylinder 4 plug and it was wet, I assume with gas. I was told that they checked the compression in that cylinder and found it to be 40psi. I asked what the normal compression should be and was told around 180psi. They then said it could be broken rings, valves or a cracked piston and a new engine might be the solution. Obviously, this was disheartening news. Also, note, I am an engineer and have been around cars my whole life. I know my way around them, from this plug and coil change to an entire K24 turbo installation on my 996TT. I started reasoning this out and was looking for all possible options that could lead to the low pressure, the misfire code and the wet plug. I realize that the above suggestions could be true (rings, valves or piston) but I also thought it could be a head gasket problem. Sidebar.... I could swear that when I started the car, right after changing the coils and plugs, that I heard what sounded like a small exhaust leak..Pfft, pfft, pfft, pfft. I bent down to the ground and and it sounded like it was coming from the bottom of the firewall, presumably where the exhaust manifold connects with the exhaust pipes to head towards the back of the car. So, in my mind, I am thinking that cylinder four is at the rear of the right bank (correct??) and the head gasket could be expelling air through it while not necessarily interacting with with block/head coolant tubes. That would explain the lack of compression, the pfft, pfft sound and the lack of coolant in the oil/oil in the coolant. I have attached a p[hoto that shows the OLD plugs and coil packs. I kept tham in the order removed from the car. I believe #4 is the right rear cylinder. You'll notice that OLD plug is black, while the others are tan. What does this typically mean? Do you guys have any ideas or suggestions? Your help would be very, VERY, much appreciated. Thank you in advance. Ken
  11. RFM, Thank you for your reply, however, my original questions are still unanswered. First and foremost, I would like to know if the GT2 pump has a higher capacity, what is the higher capacity, and would it be appropriate to move to the GT2 pump in my 600hp, 5 bar fuel pressure regulated twin turbo car. Knowing if the GT2 pump has better flow characteristics will allow me to make the right decision. I hope you can help. Best regards, Ken
  12. Wross, "7. I applied direct 12V from battery to the fuel pump terminals on the top of the gas tank and there wasn't any noise." When I applied 12V directly to the fuel pump terminals, right from the battery, there wasn't any noise from the fuel pump. I was in a quiet garage and expected to hear a "whir" or some other mechanical noise. Trying repeatedly with direct 12V gave zero response. Loren, Thanks for the excerpt. So, it seems it is not totally clear if the pump is more powerful, more efficient, pumps more volume. What is the source you referenced? I am not familiar with that acronym. Best, Ken Every year Porsche publishes a technical book that is the changes from the previous model year. These are usually called Service Technik or Service Information books. When a new model comes out (i.e. the first model year of the new model) the book is very thick and has a great deal of technical detail on the new model. Many of these books are available here for our Contributing Members. Loren, Thanks. You actually misunderstood my question though. I meant the acronym RFM! LOL I found out that RFM is a person! LOL Anyway, I look forward to RFM's insight if he is available to shed some light on the differences between the TT and GT2 fuel pumps. Best regards, Ken
  13. Wross, "7. I applied direct 12V from battery to the fuel pump terminals on the top of the gas tank and there wasn't any noise." When I applied 12V directly to the fuel pump terminals, right from the battery, there wasn't any noise from the fuel pump. I was in a quiet garage and expected to hear a "whir" or some other mechanical noise. Trying repeatedly with direct 12V gave zero response. Loren, Thanks for the excerpt. So, it seems it is not totally clear if the pump is more powerful, more efficient, pumps more volume. What is the source you referenced? I am not familiar with that acronym. Best, Ken
  14. Loren, Thanks for your response! Are you the same Loren that is friends with Cary (ERP)? I think he actually chatted with you about this. Anyway, I realize the TT vs. GT2 tanks are different and therefore, some of the parts, however, is the pump capacity different too? It is conceivable due to the GT2's higher HP value from the factory. They may have upsized the pump. I have read they have a higher capacity, but don't necessarily trust the source. I wanted to somehow get a definitive answer with flow rate specs. Can you help? Do you have this info or know where to get it? Best regards, Ken
  15. I think the pumps have the same specification, but the fuel tanks are different. The tt has 4 WD and a 63l tank while the GT only 2WD and a 92l tank. So the pumps have different installations, the tt having one piece with the tank level sensor included and the GT2 is separated. Thank you very much for the reply, however, I am not sure that is the only reason for the different pumps. The GT2 pump is $549 retail and the TT pump is $349 retail. That is quite a disparity for it just to be a different pump. I also read references of tuners changing the pump for modified cars to add extra pumping capacity with higher horsepower and greater fueling needs. So, any definitive answers to both questions???
  16. Hello all, My 2002 996TT has sat unused for 3 years. It is a modified car with 600 hp. It had very little gas in it at the time of its last use. The last tankful was 100 octane GT100 from Sunoco. The fuel light was on when it was last used. I decided to get it back on the road recently and found it will not start. I did the following so far: 1. I added drygas and a half tank of 93 octane fuel. 2. I removed the air filter (modified cone filter) and sprayed starter fluid into the velocity stack where the MAF sensor is located. The car started and ran for 5 to 10 seconds. 3. I know I have spark since it ran briefly. 4. I cycled the key on and off about 20 times (not engaging the starter) thinking I would "prime" the system with the fuel pump. The car did not start. 5. I pulled the fuel pump relay and tested it. It is functioning properly. 6. I disconnected the fuel pump harness connector in the front trunk and connected it to a test light. I turned on the car as if to start it and the test light turned on. This means the fuel pump is receiving 12V. 7. I applied direct 12V from battery to the fuel pump terminals on the top of the gas tank and there wasn't any noise. 8. I am convinced the fuel pump is the culprit. If you agree with my assessment, please respond. If you think I missed something, please enlighten me. Doing further research, I found that there are three fuel pumps listed for the 2002 996TT and GT2 in Porsche PET. There are two listings for the 996TT: Part #99662010700 (Comment "/LL") Part #99662010800 (Comment "/RL") There is a single listing for the GT2: Part #99662005790 It is my understanding that the GT2 fuel pump has a higher capacity. So, I have two questions....................... Q1: Does the 996GT2 fuel pump have a higher capacity than the 996TT? If so, what are their comparison specs in XXX LPH (Liters per hour) at YY pressure? (Example 200 LPH at 5 bar) If it does, I would probably want to install the GT2 pump since I am already running the 5 bar Fuel Pressure Regulator (as compared to the factory 3.5 bar unit). Q2: What is the difference between the two 996TT part numbers listed above and what do "/LL" and "/RL" mean? I would appreciate any help that anyone can provide. Thanks, Ken
  17. Loren, You are a godsend. I thought it was that easy. You want to be sure you know. Thanks!! BTW, great site! Keep up the good work. Regards, Ken
  18. I recently converted my 2002 TT center radiator to the angled GT2 type of setup with all associated ductwork. In order to do so, I had to drain the center radiator as well as whatever came out of the two feed lines that connect to the front radiator. I have added 2 liters of Porsche coolant and almost 2 liters of plain water (for a 50/50 mix) but it appears more came out that went back in. That judgment was purely subjective. I did not measure. I would like to know the correct procedure to burp the system. Any help would be extremely appreciated.
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