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I suspect that Andrea quoted for the pair rather than the one I need. My local AdvanceAuto list a Denso as direct fit at $106. Would it be a problem to just replace one with a Denso? Steve

$200+ for one pre-cat sensor on my 2006 turbo. Anybody have a cross reference part number from one of the usuals? I am sure that NAPA only wanted $80 or so last time I asked but I want to make sure I get the same connector as the OEM supplied unit Steve

I have been posting my problems for a while. Starting with random and persistent misfires on one bank (5-8). I have replaced all coil packs and plugs and the problem is less frequent. After a couple of days poor running I ran my Durametric to get the following codes.... P1549: Vehicle electrical system voltage via main relay - No signal/communication, test conditions are not-completed, fault is currently active and is not causing a DTC light P2146: - Upper limit value exceeded, test conditions are not-completed, fault is currently active and causing a DTC light P0150: O2 Sensor Circuit Bank 2 Sensor 1 - Implausible signal, test conditions are not-completed, fault is not currently active and is not causing a DTC light Can anybody help me identify an underlying cause(s) Steve

Many thanks - I found it. The rubber hose is still not prepared to budge so I will cut it off and replace it as the easy solution. Parts arrive tomorrow and hopefully I will be driving her again this weekend Steve

...replace all of the coils (not just a few)and do the plugs at the same time. I stayed with the OEM Beru plugs from Sunset Porsche as the last set did 100K as far as I can tell. Get a Porsche dealer to give you history on the car and you may find (as I did) that the Cardan shaft and plug packs have already been changed Steve

...and check/replace fuses 7 and 8 in the E box under the hood Steve

...This should be easier than it looks. I have removed the pressure hose from the turbo (cylinders 5-8) and noticed that the aluminum casting between the pressure hose and the turbo has some play so while I was doing the job I thought I would replace the rubber O ring at this joint. Unfortunately, the casting has a short rubber hose attached going to what looks like a vacuum control pod and there is not enough movement in the hose to pull off the casting to get to the rubber O ring. I loosened the clamp at the vacuum switch but the hose but it wont pull off and I don't want to break the plastic fitting. Is the only answer to cut the hose and then replace it? All advice gratefully received Steve

I finally finished the service and then removed the inner wheel arch to get at the turbo pressure pipe which was covered in oil thanks to a leaking Henn joint. The hose elbow contained about a quarter pint of oil which had been making its way as a mist through the cooler into the throttle body. I have ordered a new pressure tube from and O ring from Andraya and will re-assemble when it arrives. It is a great opportunity to clean everything up but I am not looking forward to putting the wheel liner back in - it was a bugger to get off..... Steve

The best tool buy I ever had was a set of pliers including large, long nosed straight, another pair with a 90 degree bend at the end and another pair with an open circle at the end of the nose. This latter set is what I use to pull the connectors off the plugs, they fit perfectly around the upper part of the connector without straining any wires and the plugs come off as easy as pie. I also use them to pull out the coil pack as they grip nicely around the middle of the square section. Because of their shape, they are also ideal for tugging and pushing variuos diameters of rubber tubing. Steve

That is good info and a salutary tale. I did check and clean the grounds. I have changed the fuses on several occasions now and see no signs of overheating or damage on the fuse or the topside of the fuse box. The schematics do not unfortunately show the connectors in the junction box, only the lines from coil packs/injectors to the fuses but I will trace them from the color codes. At least my problems are presently intermittent on one cylinder only (5) and only at idle which might indicate a ground problem somewhere. It also occurs to me that the O2 sensors are cleaning themselves up since I changed out the coil packs and plugs and the problem might eventually sort itself out (clutching at straws now). In the meantime, I have started a service which will now not be completed until tomorrow because I was given the wrong oil filter. I will also clean the air intake and turbo pressure pipes out in the event that the remaining issue is due to oil contamination. I will clear down all off the codes after I finish and take her for a long run and report back with my findings. I really appreciate the support from you guys. This has been such a trial that I suspect a dealer visit would have brought me to the edge of bankruptcy. Regards Steve

Thanks - I already did that so I am wondering if it could be a bad connection under the fuse box.... Steve

Today, the car behaved reasonably well. Misfires seemed to occur mostly at closed throttle. Raising the idle just a couple of hundred revs stopped it. I will be servicing the old girl tomorrow and plan to clean the air tube from the turbo on the drivers side at the same time. I know she has been blowing oil up to the intake and want to make sure that I am giving the cylinders at the front of the car their best chance to fire. Wvicary = what would you recommend to deal with the fusebox issue? Electrical contact cleaner? Can you tell me how to remove the fusebox so I can check the connections underneath? Thanks again to all of you for your advice. Steve

Thanks for hanging in here with me. I spent a couple more hours on it today and it looks like the problem is in the fuse box. The misfires are moving around between cylinders 5-8 and so I opened up the top of the E Box and started tugging at wires that I could get to. Occasionally, the problems cleared up, only to come back after 10 minutes driving. If somebody can advise on the best way to remove this fuse box, I will check out the connections underneath it. Also, does anybody know if any of the colored connectors next to the fuse box carry the coil wired for this bank and if so, which? I checked cylinder 5 plug using one of the old coil packs running a separate ground from the plug and it has a nice strong spark. I can also hear the injectors running nicely using a screwdriver between the injector and my ear. Steve

Binger The original codes suggested a problem with coil pack 7 and/or a short in the coil pack system. I checked the wiring by unwrapping the insulation but found no problem in the wiring and so re-wrapped. The fuses were also good in the E-box though the problem went away for a couple of weeks after replacing them which I suspect is coincidental. The connectors all seem tight. What is very odd is that the problem migrates from cylinder to cylinder but always on that bank. Today, I plan to lube the silicon seals in the connectors and re-connect them. I will also use one of the coli packs I removed to check for a spark outside the cylinder. At least I will be able to see if the spark is strong and/or not present at all. Because I don't know how the computer detects the misfires, I still am not sure if the problem may be related to the injectors. Can you shed any light on this and how I might be able to discount injectors as the problem. I have not seen anything on the Durametric which points in this direction. Steve

Porsche parts only and I double checked everything when I assembled it. My suspicion is still a bad connection somewhere but not sure how it hits two cylinders (though 5 is now missing most of the time) Steve

I am utterly frustrated. I replaced all of the plugs with new Beru ones and the remaining 4 coil packs. The Durametric is now reporting a constant misfire on 5 and a few on cylinder 6. As requested, I logged the session and mailed to Durametric. Monday, I will go back to the indie and see what they say but this time will look at the scan while they are doing it Steve

Unfortunately, I took a Durametric reading just before I took the car down there and it was still showing the cylinders 5-8 as problematic. In fact, when I looked at some actual values for cylinder misfires I could see them racking up on the same cylinders as I watched. Very curious. I will report back when I get the new parts in (probably this weekend Steve

Thanks JFP - I had already checked that the manual supported my view. Durametric is looking into the issue for me. If the problem is still there after I replace the remaining parts, I will go back to quiz the mechanic Steve

I must have caught Andraya as she walked in and she had the decimal in the wrong place. New one ordered at #143..... Steve

I have been posting for some time about serious multiple misfires on one bank of cylinders. The problem was intermittent but always on cylinders 5-8. Eventually, the problem got so bad I took it to a local independent dealer. Before this point, I had refreshed all vacuum connections,unwrapped and re-wrapped the wiring to all of the coils and injectors, replaced the coil packs and plugs - all on the one side reporting the problems. I didn't do both banks immediately, but planned to "catch up" the work later when the problem was resolved. Oh...I also replaced the fuses 7 and 8 in the e-Box. So the dealer put on his PWIS and after 20 minutes or so comes back and asks which side I had replaced the coil packs and plugs. Drivers side, said I. He went back out to the car and returned with the key a few minutes later, talked with the boss and left. The boss then told me that I was a good mechanic, had diagnosed the likely fault and taken the right steps - on the wrong bank ! He also said that I should only replace coil packs and plugs in a full set (which I knew anyway). I was a bit embarrassed and got out of there after paying $40 for the diagnosis. When I got home, I pulled the error logs from my Durametric and also the cars manual. I am not crazy, the reported errors are on cylinders 5-8 and they are on the drivers side. Being a careful kind of cove, I then started pulling the coil packs and plugs on the passenger side to find the plugs were absolutely shot and bright white with lots of residue. It seems very likely that the problem was indeed on the passenger side bank. Either.... 1. My Durametric is wrongly reporting errors on the other side or 2. The manual is incorrect and the plugs are numbered 1=4 on drivers side, 5-8 on passenger side 3. There is a problem on the other bank which my Durametric could not identify 4. I am completely nuts. I have ordered the remaining coil pack and a full set of Beru plugs and cant wait to see if it fixes the problem which has plagued me for weeks if not months. In the meantime, I open up the floor for suggestions, comments, insults... Steve

I have already been contacted and have to submit the claim (parts and labor) by this time next year. They are offering 25% of the cost and that is prorated by the mileage on the car. As I did the work myself, I can only claim 25% of the value of the parts. I suspect the lawyers will do better out of this than we will Steve

That nice piece of Magnesium alloy that goes between the head and body has a torn rubber bush on the body side and the other one doesn't look that healthy either. I just spoke with Andraya at Sunset and she tells me I can only but the complete thing for about $1150 !! Has anybody ever sourced the replacement bushes and if so from where? If I have to I will find a round rubber bush with same inner and outer dimensions. Not as sophisticated but $1150 !!!! Steve

After looking at the wiring diagrams the fickle finger of fate pointed at fuse 8 in the E box. Oddly enough, this fuse feeds coils and injectors for 5,6, 8 and 3. In going back to look at my errors almost all of the misfires causing the DTC light were on 5 and 6 and now 8. I removed the fuse (again), replaced it (again) but with significant wiggling and now the errors have gone. I have been disappointed before but it seems likely that this circuit is the culprit. I will put some miles on her tonight to see if the problem stays fixed before ranting here again Steve

Don I already did that. My Misfires are all across one bank (5-8) and at different times, higher misfire rates on individual plugs. Playing with the harness appears to make no difference. I am starting to think it may be a grounding issue, an O2 sensor or a problem with the DME. I have never had to give up on this kind of issue before but I think this is one for a PWIS readout - Durametric just isn't giving me enough data to target the source. It is very frustrating Steve

Hi Loren P2228 did occur once before but seems to be an aberration as it does not usually come back after reset. After another couple of hours on it, I discovered that when I disconnect the injector for 6, 5 stopped firing. This might not be surprising if either of the two injector wires are daisy chained but after reconnection cylinder 6 which was hardly firing at all has now started behaving itself with only an occasional error and now cylinder 5 is not firing. At this point it definitely feels like a short somewhere in the injector harness. Any ideas what to try next? Steve