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ianwallwork

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Everything posted by ianwallwork

  1. RedRidge Using hi-flow (200-cell / 100-cell) cats requires a re-map to work properly for exactly the same reasons as a cat bypass. You are changing the operating parameters of the engine. If it flows more exhaust gas more easily as rpms and throttle openings increase then the timing requirement will be different. This effect will be less pronounced with free-flow cats than with a bypass as the increase in flow will be less. Whilst a properly re-mapped ECU will still bring the most benefit, the timing difference required may be small enough that you may still see (an albeit smaller) power increase with the standard map. As an aside (and just to confuse everyone for a moment.....!) we also have no way of knowing how 'accurate' the standard mapping might be. If it is particularly conservative (normal with many manufacturers for reliabililty) the standard timings may even turn out to be closer to the optimal real-world requirement with free-flow cats / headers etc. at some points in the load vs rpm range. This cannot be relied on however and you will certainly get inconsistent results with a standard map and modified components. What you DO gain by using high-flow cats is that the post-cat O2 sensors are now back in the loop correctly. I would recommend using 200-cell cats for road as they don't boom and resonate like 100-cells can. Phillip A worthwhile tuner will offer a range of packages that include known mods and an ECU to match. AFAIK, Fabspeed offers a range of modded ECUs to match their products. Please post the results back - it will be interesting to see how you get along. Ian
  2. Phillip Removing the Cats has two major effects. First one is that the post-cat O2 (lambda) sensors are going to detect 'unclean' emissions - they usually are subjected to exhaust gasses that have been through the Cats and are 'cleaned' - this may well cause the ECU to go into some sort of safe mode due to it thinking your cats have failed. Second (and assuming that the first problem is properly resolved) removing the cats reduces exhaust back pressure as the volume of exhaust gas increases. (Even inefficient, standard cats will flow a small volume of gas without creating back pressure, the pressure starts to build as throttle/revs rise). This change in back presure will affect the scavenging of the combustion chamber (i.e. more exhaust gas will escape on each exhaust stroke) allowing more new mixture in. This is good and will theoretically allow more HP to be produced. HOWEVER....... You now have an engine that is breathing and burning more effciently. This change in the engine's operating parameters means that your standard ignition timing will be way out. Ignition timing at full throttle depends, amongst other things, on the volumetric and burn efficiency of the engine at any given point in the rpm range. Typically an engine that is breathing and burning better requires a SHORTER ignition advance curve. That means the ignition needs to happen later in the cycle - yes, LESS timing. This is simply because a more efficient, cleaner burn happens more quickly and therefore needs to be ignited later for the maximum pressure to be applied to the piston at the optimal point on the power stroke. The volumetric / timing-requirement differences made by removing the cats will not be huge (compared to say, gas-flowed heads and new cams) but could require a timing compenstation of up to 5 degrees or so. Using the standard mapping, you would notice this as slightly reduced power - and inconsistently so across the rev band. If you are noticing big power drops then there is something in the ECU shutting down / gong into safe mode because it senses cat failure. In short then - if you make mods, you must have a re-mapped ECU designed to take account of EXACTLY those changes you have made. Mod + matching-ECU are an inseparable pair. Any mod renders the standard engine mapping wrong to a greater of lesser degree. And if you change something that takes a sensor out of its operating range, the sensor will need to be taken out of the loop in the ECU too - either deactivated or given a new set of expected values so it doesn't interfere with correct operation. Hope this helps Ian
  3. Do you have a link to the manufacturer site? - I really like the look of these wheels and would like to enquire if they're available in the UK Many thanks Ian
  4. The Variocam Plus changes the inlet cam timing at around 6000rpm on a 3.6 (The 'Variocam' bit of Variocam Plus). If you are getting problems only above 6000rpm this is the most likely cause. It also switches from the mild to hotter inlet cam profile at about 3400rpm (the 'Plus' part of Variocam Plus) - you can usually feel this at part throttle. If that wasn't working, it would strangle the engine completely from 3500rpm up . If it was a bad MAF, it would make itself felt any time the engine is not running closed loop which is mainly at or near full throttle at any rpms. Again this doesn't fit the symptoms exactly. The PST-2 / PIWIS can test the Variocam operation in seconds. Best take the car to your stealer!! Ian W
  5. That is often indicative of MAF failure. I think your best bet is to get the codes read by your dealer or a good independent. They will then be able to investigate further and correctly diagnose the problem. Both the MAF and lambdas tend to have a relatively short life on 3.4-litre cars.
  6. In answer to your questions, no the leak will not cause any problem or performance penalty. To stop the leak, simply get two new clamps. The old ones are probably distorted - mine were when I took them off when fitting my PSEs. Also the spec has changed - the new ones now have bigger / stronger bolts and seal better. Also torque up the clamps before fully tightening the 3 nuts that hold the silencers to the car. On a different note, don't forget to reset your DME now you have the new exhaust cans. This will cause the unit to recalibrate and you will quickly see any performance gain the exhaust might bring. To reset the DME, turn your ignition to 'on' (all dash lights on but motor not running). If you don't do this the alarm will go off. Then disconnect the negative battery terminal. Turn the ignition off and leave the battery disconnected for an hour or so. Re-connect and go for a drive and I think you'll be very pleasantly surprised! Ian PS. After you've re-connected you'll need your radio code as it will ask for the pass code. You'll also need to run your windows up and down a couple of times before the one-touch will work.
  7. I think you have a MAF that's close to failing. What I think is happening is this: when your CEL light was on, your MAF was not functioning properly and the car was running on the in-built pre-determined fuel map it uses if there is a MAF fault (If you completely disconnect the MAF you can still drive the car apparently normally because this map exists). When the codes were cleared, your MAF was brought back into play. If I'm right and its calibration is wrong, it was causing your engine to be fuelled wrongly and you noticed this as a drop in performance. When the CEL came back on the MAF was disabled again as the DME saw it as faulty. The engine reverted to running on the pre-determined map and you got back the missing power. Another possibility is failed lambda sensor(s) in the exhaust. The DME uses the feedback from these sensors to continuously correct the mixture at part throttle and also uses the correction information gained over time to calibrate the MAF sensor. New lambdas and/or new MAF should have the car running like new. Ian
  8. This will be caused by the brake light activation switch being faulty. This sits behind the bottom of the dash over the brake pedal. They're notorious for failing on pre-facelift cars - I even used to keep a spare in the car!! No problem with the current car so maybe they were changed for 2002. The part is cheap, fitting time is approx 1 minute. Hope this helps Ian W
  9. Hi MM If you buy an extended warranty from Porsche, your engine will still be covered and replaced if it lets go. If it works the same way as the UK extended warranty, you just need to apply before your factory warranty runs out and no vehicle checks are required. So go for the extended warranty (irrespective of whether the separator fixed the oil consumption problem or not). Broken engines are then Porsche's problem and all you have to do is relax and enjoy driving the car like you stole it!! Ian W
  10. The separator can be replaced without the engine being removed. My old 3.4 had this done once (and the oil return bellows - a flexible rubber tube attached to it that returns oil to the sump - replaced several times) by my local specialist. Pain to get at and probably 3-4 hours plus parts but not as bad as an engine out. Ian W
  11. The Fabspeed airbox mod wouild be a better bet. It removes the muffler inside the airbox and gives you better sound. No noticeable increase in power though (I know because I've fitted them to both my old 3.4 and current 3.6). I would also stay with the standard Porsche air filter. On a standard car, these are as good as K&N etc. if they are replaced regularly (paper filters clog up more quickly and their performance goes off noticeably). The upside is they cannot contaminate your MAF sensor as oiled filters can. Ian W P.S. The Fabspeed airbox mods sound superb on the 3.4 and less so on the 3.6. They also sound dire with the PSE as the sounds produced by each clash horribly. Sounds very good with Fabspeed mufflers though.
  12. Hi Joe This shouldn't have hurt your engine at all or logged anything in the DME. If you hang on all the way to the 7300rpm limiter (7300rpm is still safe but the max safe speed the engine will go to) in second it equates to approx 74mph. If you dropped it into 2nd by accident at 60-65mph this will not have caused the engine to rev anywhere near 7300rpm. In fact it will only have revved it to between 5900 and 6400 rpm if you work out the math. This is way under the max safe revs and no harm done. Ian W
  13. The Fabspeed intake sounds superb on the 3.4 but produces no extra power. Not surprisingly, the sound liberated by the Fabspeed intake matches the sound of their mufflers very well indeed. (The mufflers sound really good on the 3.4 too and do produce extra power). Loved my old 3.4 in this configuration On the 3.6, it makes the engine sound awful (very flat sounding). My car has PSEs though and it could be the combination of the intake and PSE that just didn't sound right. The intake and Porsche mufflers have sounds that are at slightly different frequencies and they simply don't work together well. It may sound much better with Fabspeed mufflers but I've never tried this combination on the 3.6. I also felt that the 3.6 lost significant power with the intake fitted - the reasons I can't even guess at but it was quite noticeable. I would also advise you to ignore the bit in the instructions that tells you to remove the flow straightener in the intake and replace it with a silly little carbon-look plastic ring. The flow straightener ensures the airflow over the MAF is even and can cause part-throttle fuelling issues if removed. (The O2 sensors will compensate to a point but can end up going out of range if they have to compensate too much). Also don't use with an oiled filter (K&N for example) as the oil they're impregnated with can kill MAF sensors! Ian
  14. Regarding the 'flat spot', the torque curve of the 3.6 engine has a noticeable dip between 2000 and 2700 rpm. If you floor the throttle at low revs (under 2000) the car will initially accelerate well, you will then feel the acceleration tail-off noticeably between 2000 and 2700 and then the torque comes back in again as you approach 3000 rpm. You will then feel a 'bump' at approx 3300 when the variocam plus switches to the higher-lift cams on the inlet camshaft. This behaviour is entirely normal. Ian W
  15. Had Fabs on my last Porsche - '99 C4 - sounded amazing! A little too much around town but at WOT simply awesome! Despite my really liking the Fabs, I had the latest PSE fitted to my '02 C2 last weekend (simply to avoid potential warranty issues in the UK - Porsche GB are a bunch of a**holes compared to Porsche NA). This latest PSE (or may be v3 - not sure) is every bit as loud as the Fabs and frankly doesn't sound as sweet as the earlier versions. Can't say I'm totally disappointed but I expected something more melodious and less obtrusive. This version is also very 1-dimensional in the sound it produces. Earlier ones produced such a rich variety of sounds - this is just uniformly loud once you're on the gas. All in all, I could take them or leave them. I think your sports exhaust money would be better spent on the smaller, lighter, less expensive Fabs. (Porsche GB's attitude not withstanding). Ian W
  16. dj996 The exhaust gasses apparently take a different (if only shorter) route through the muffler to exit at the top rather than the centre of the can. When the valves are closed, the gas goes through an additional chamber - hence quieter - and exits through the middle outlet like standard. This was confirmed by another Porsche Club GB member who had seen a new-style can opened up but I can't find the thread just now. Will add it to this message when I find it Loren, Do you have any details of the differences between all three 996 PSEs? The early type is obviously visibly different to later ones but I wasn't aware there were two later types. Any idea what they changed and when the changes came about? Hope you can advise Ian W
  17. The later PSE completely re-routes the exhaust gasses through the muffler and through a different, full-size outlet pipe altogether when in loud mode. this is spliced into the part of the muffler that the tailpipe attaches to. This later-style PSE on a 3.6 feels like it produces a little more and at least one member of the UK Porsche Club (see post from Ess_Three in this thread: http://www.porscheclubgbforum.com/tm.asp?m=99681 ) has reported over 10BHP increases on the dyno. Has anyone else had a before/after dyno run with the latest PSE? Ian W
  18. Interesting! EXACTLY the same problems I had with my last P-Car (a '99 C4). Split oil filler pipe and failing bellows (3 times on mine)! Ran like a dog at part throttle until the air leaks were sorted. Then ticked over fine but still no good at full throttle. Guess what? Yup, MAF!! As you said - like driving a new car once this is replaced. The issues with deteriorating MAF sensors are genuinely dangerous IMHO. At part throttle, the MAF measures the amount of air entering the engine and the DME calculates the fuel required to deliver the correct mixture. This is then 'checked' by the lambda sensors and corrected in 2 ways - a 'long term fuel trim' that tends not to vary much and compensates for manufacturing tolerances in the MAF and a 'short term fuel trim' that instantaneously corrects the mixture and goes up and down like crazy!! This correction ensures the part throttle mix is OK even if the MAF is off calibration by a small amount. Once above part throttle, however, there is no mixture correction by the lambda sensors and the MAF governs air/fuel ratio. If it is out of calibration, a lean mix will result. Performance suffers and more importantly LEAN MIXTURES BURN VERY HOT! And this at full throttle when the engine is being worked its hardest. This fault can cause local or general overheating and I wonder if it is in-part responsible for some of the engine failures we read about? My engine had always run a little too warm on the gauge and this stopped immediately on replacement of the MAF. Anyone else experienced similar? Ian W
  19. Does anyone know if it possible to have PSM retro-fitted to a MY2002 Carrera 2? Thanks in advance Ian W
  20. Rather than using an injector cleaner, I recommend using Shell Optimax gas in our P-Cars. I understand this is being launched / has just been launched in the US under the name 'V-power'. If it mirrors the product available here in the UK it will make a very big difference to how your car runs for a couple of reasons: 1) Optimax has a mix of additives that both cleans injectors and removes deposits from inlet valves improving performance but acts continuously unlike an occasional dose of injector cleaner. A UK magazine tested this claim a year or so ago using a bore scope to look at the deposits on inlet valves both before and after 1 month running on the Shell gas. In all cases the inlet valve deposits had all but disappeared. 2) The UK version of the product (Optimax) is 98-RON. As I understand it, most US pump gas is normally 93-RON (standard UK pump gas is 95). According to the owners manual for my MY99 C4, the maps in the ECU are designed to produce the car's rated power using 98-RON gas. If the RON is lower than this, the knock sensors back-off the timing as required to prevent knocking (and engine damage) but lowering power and (in particular) low end torque as aresult. If the US 'V-Power' version of Shell's product is also 98-RON you will see a very noticeable performance increase from using it. I have noticed a significant difference against normal UK 95-RON fuel. Please note however that you will need to reset your ECU to take accont of the higher octane fuel. I would suggest filling the tank with V-Power, running until the tank is almost empty and re-filling with V-Power. This will get rid of older, lower octane fuel from the system. Then disconnect the -ve battery lead for a few seconds - that will reset the ECU. Fire the car up (you may notice a slightly lumpy tickover for a while as the system re-calibrates) and then enjoy! Ian W PS For clarity, I have no connection with Shell, just a happy customer.
  21. Does anyone know if it's possible to retro-fit a PCM-1 unit to a 1999 C4? (I'm assuming here that PCM-2 is not compatible with earlier cars). If it is possible, does anyone know where I might get one (I'm in the UK in Manchester). Hope you can help Ian W
  22. The job can be done with the engine in the car but is DEFINITELY not a DIY job. I've just got back from my local Porsche specialist who is (amongst other things) replacing all the hydraulic tappets in my engine. The cam covers are currently off with the engine still in the car. BUT... The rear engine mounts have to be removed and the rear of the engine lowered and supported to give clearance to remove the covers, the entire exhaust system including the headers has had to be removed, the rear wheels removed, all the coils and the heat shields have had to come off the engine, the variocam sensors removed and several Porsche special tools inserted. The first of these stop the cams being forced out the engine by the valve springs (this totally destroys the chain-end fixed bearing if you don't have the tool and requires a new cylinder head). the others maintain the tension on the various cam chains. So, in short, this is a MAJOR job and way beyond the realms of DIY. Sorry the news isn't better! Ian W
  23. I think your comments about the smile returning will be correct - I've tried so hard to keep a sense of humour about all this! Just wish the **** car would work properly as I'd prefer to be driving across Europe in it rather than just to the nearest garage!!! Think you are also right about the level of warranty and good-will offered by Porsche GB. Love the comments about the 'Fiat'. Hilarious and true! Ian W
  24. Thanks for the responses. Some points to note 1) The car was sold privately and I know the previous owner's family (she is a woman in her late 50s who drove the car relatively gently) 2) I know the Porsche dealer where the car was maintained and they confirmed the service history 3) I had the car inspected by a very reputable local Porsche specialist (owned by a fully Porsche-trained technian who used to work for the dealer that serviced the car) The specialists also prepare and race 2 of their own GT3s and also offer technical support to Porsche motorsport in the UK. 4) The car was in reasonable condition when I bought it! There were a couple of small issues, yes, but it is a 60k miles car so these were expected. 5) I don't track the car but drive it reasonably hard on the road (where appropriate). So it's hardly heavily stressed! 6) Pay to play.....Umm. Yes I agree to a point. Had I bought the Ferrari F355 I was going to buy then i would have expected very large maintenance bills - fair enough. And with a 60k miles Porsche I would have expected some component wear and tear (new disk rotors, suspension bushes, clutch, wheel bearings, etc. etc.) and would have no problem whatsoever with this. High performance cars cost , I agree. But this brings me to the core of my argument... What I have experienced is not normal wear and tear!! I have been unlucky, sure, but that is life. My point and the reason for my 'pissy' first post is that all the problems I have had to deal with (and it's been the inability to use the car, not the cost, that has really annoyed me) have not been down to usage of the car. They are almost all design flaws!!! If a car has been used gently by a first owner and serviced religiously in-line with the manufacturer's guidelines then itt is not unreasonable to expect it to work correctly; perhaps other than items that one would expect to wear or have a tough time with the miles the car has done. RMS, header tank, cam cover seals, bellows, strut tops, oxygen sensors, windshield surrounds etc. have all been the suject of re-designs and Porsche are having you, me, third-party warranty companies, whoever, pay for their less-than-perfect engineering. My car is only this unreliable because it was designed that way!!! It wasn't the previous owner's fault or mine or the garage's or the person who inspected it - it was Porsche. Isn't it about time they took some responsibility for known issues and had a proper policy of assisting owners who experiece these failures? Ian W
  25. Can anyone beat mine for never-ending problems? Failures are listed in my signature and all this in 4 months!!! Car is currently at the local Porsche Specialist having the hydraulic tappets on both banks replaced, the second replacement RMS fitted and the cam cover seals renewed. (Oh, and the front suspension strut tops replaced too). Another week without the car. Pi**ed at Porsche is a major understatement! Would like to get everyone that has had a number of issues with the cars to list them here as I intend to send the lot to Porsche AG. Anyone thought of a class lawsuit regarding the design faults in these cars that Porsche merrily allow their customers to pay for? Ian W
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