PKN

Looks like re-wrapping my ignition/injector harness did not solve my problems. I am still getting intermittent misfires. Always on cylinders 5-7 and usually only when the engine is warm. I have changed plugs and coil packs and also checked for vacuum leaks. The latest codes are

P1132:
- Value below lower limit value, test conditions are not-completed, fault is currently active and is not causing a DTC light
P2228:
System Off Idle Bank 2 - Value below lower limit value, test conditions are not-completed, fault is currently active and causing a DTC light

Any ideas anyone?

Steve

The problem is apparently fixed. I plan to remove the insulation on the other bank soon to look for similar issues before they become a problem. 100,000 miles seems to be time for a few more inspections than I had planned. Changing out the problem harness is not an option as Porsche does not list "part harnesses", only the bits that attach to it. Maybe its time to look at adding some extra airflow under the hood via a scoop or something. It is getting monotonous, changing out vacuum tubes, cooling tubes, coil packs and now wiring.....

Steve

Check my post below about multiple misfires. Mine was apparently caused by split insulation on one of the coil packs which shorted out the whole bank. My car also has 100,000 miles and my cure was to remove the tape insulation and repair the damaged wires. I suspect prolonged heat caused the insulation to become brittle. The car runs fine now

Steve

Today, I disconnected all coil packs, injectors and associated sensors and unwrapped the insulation, cleaned off the wires and closely inspected them as well as all of the connectors. I found only two small areas where the cable cover had split and one of those was a ground wire. The other was to a coil pack - number 7. I could not see anywhere it might have grounded. I wrapped the problem areas and reconnected everything. Testing the motor with the Durametric I got no misfires over a 5 minute run. I re insulated all of the wiring and retested. No errors. Put all of the covers back and retested - no errors.

She is running very smoothly now which leads me to believe that either a connector wasn't seated right or the insulation break caused the problem. I will put some miles on her tomorrow and report back. Cant say I am happy that I didn't discover a definitive cause for the problems but will take the result and hope it stays fixed. A good day. I even got the chance to finish reassembling the rear windows and hatch on my Jag XKE....

Steve

This morning things went from bad to worse...below are the error codes I got on the Durametric. It sure feels like a short in the wiring harness ! I am thinking about removing this part of the harness and stripping off the insulation to check it out....Any other thoughts? So far we have new fuses on 7 and 8, new coil packs (latest revision), new plugs and even some injector cleaner in the tank

P2320:

- Upper limit value exceeded, test conditions are not-completed, fault is not currently active and is not causing a DTC light

P1132:

- Value below lower limit value, test conditions are not-completed, fault is currently active and is not causing a DTC light

P2228:

System Off Idle Bank 2 - Value below lower limit value, test conditions are not-completed, fault is currently active and causing a DTC light

P0300:

Random/Multiple Cylinder Misfire Detected - Value below lower limit value, test conditions are not-completed, fault is currently active and causing a DTC light

P0306:

Cylinder 6 Misfire Detected - Value below lower limit value, test conditions are not-completed, fault is currently active and causing a DTC light

P0305:

Cylinder 5 Misfire Detected - Value below lower limit value, test conditions are not-completed, fault is currently active and causing a DTC light

P0307:

Cylinder 7 Misfire Detected - Implausible signal, test conditions are not-completed, fault is not currently active and is not causing a DTC light

P0301:

Cylinder 1 Misfire Detected - Value below lower limit value, test conditions are not-completed, fault is currently active and is not causing a DTC light

P0307:

Cylinder 7 Misfire Detected - Value below lower limit value, test conditions are not-completed, fault is currently active and is not causing a DTC light

P0308:

Cylinder 8 Misfire Detected - Value below lower limit value, test conditions are not-completed, fault is currently active and is not causing a DTC light

Binger - its in the thread below - "P2320 error code and bad misfire/backfire.....help! "

The difference now is that the problems moved to cylinder 5 and on the last test run, I got no codes at all but cylinder 5 is still getting a lot of misfires. I think my next move is to run some injector cleaner through the fuel system....unless anybody has a better idea

Steve

I installed the new latest rev plug packs and plugs, checked that all plug pack connectors are undamaged and I am still getting serious misfiring on cylinder 5 - over 100 in a couple of minutes running - but the Durametric is not showing any error codes. I can see the misfires when I look at the misfire counter. If the injector is the problem, would it throw an error code? Not sure what to check next

Steve

Thanks for the help Loren. I will order the coil packs tomorrow but shouldn't I have got a different error code after I moved the coil pack? I just celebrated 100,000 miles on the old girl too. I would hate to change the coil packs and find the problem is in the wiring!

Steve

I took another look at the plug packs and discovered 3 other numbers. They are - 948 602 104 05 and 0 040 102 002 All of the plug packs on the left bank share these numbers with the one above BUT three of the four also have the designation 076B9 except fot the one fingered by the error code which is 076A9 Coincidence?

Steve

Thanks - I swapped coil packs 6 and 7. Curiously, the problem is not as bad but still there and still throwing error code 2320. Most misfires are now logging to cylinder 5. I checked the wiring as far as I am able without cutting back the sheath and all look good. I did find what looks like a burn mark on the metal cover mount close to cylinder 5 but no evidence on the wiring. The number on the coil pack is 2 303 590 361 by Beru

Steve

Loren

Many thanks for the quick response. Fuse 7 is OK so now I will start hunting through the wiring under the covers and try swapping coil packs. I am not sure if the problem will move though as I am getting misfires logged on cylinders 5, 6, 7 and 8.....

Steve

I think my vacuum circuit problems are fixed (pump runs occasionally and circuit is holding vacuum) but as soon as the engine gets warm I am getting bad misfires across both banks. Can anyone help me track this down? For the record, all the coil packs were replaced according to dealer records

My Durametric is showing the misfires as well as this code P2320 which appears to be related to a coil circuit.....

Thanks in advance

Steve

I found no less than two broken vacuum pipes down behind the servo pump. I replaced the broken pipes with 3/8 compressor hose with steel fuel pipe inside it to stop it collapsing and used clamps on every joint. I had everything I used to hand so it cost me only time and I suspect the repair will outlast the original parts.....

Steve

I had exactly this problem after getting coolant into the switch on the side of the tranny under the car. Flush the mechanism with water and let it dry out. Mine came back to normal but you need to fix any leaks you have or it will come back. I have also had a similar problem after getting a nickel inside the console. I had to take the whole thing apart to get it out!

Good luck

Steve

My problem started with the brake booster fault light followed quickly by the engine check light. The car started misfiring badly. I checked the usual places for broken hoses and found one down by the brake booster. I repaired it, cleared the error codes and the servo error light came back within a couple miles. I cannot find any more broken or damaged pipes but the misfires are very bad now and the Durametric is showing them on 4 cylinders (both banks). It almost feels like there is water in the gas. The car runs reasonably smoothly over 2000 rpm. Any ideas where or what to check next?

Thanks

PKN

Thanks again Loren. It would help if I was looking at the correct side. Still not sure of the best way to get to it - from underneath?

PKN

Loren

Many thanks for the rapid response. I will check the fuel injector connections and switch out the 02 sensor before the cat on the passenger side of the car. Can you advise if I need to get at the sensor from under the car or can it be done through the wheel arch liner. Too damned hot to go near it right now....

PKN

Gentlemen

My 2006 Cayenne TT is throwing codes and engine fault light is on. The codes from my Durametric are as follows;

P0150 - O2 Sensor Bank 2 Sensor 1 upper limit value exceeded

P2146

Neither faults are currently causing the CEL and it might take a few days after cancelling the fault before they show up again. My engine had done over 90,000 miles and I am suspecting the 02 sensors are coming due for replacement.

My local autoparts store had one Denso 02 sensor compatible with my car for pre-cat so I bought it. I don't want to fit it though unless one of the old pre-cat sensors is bad. They did not carry a Bosch in stock and it is a lot more expensive than the Denso which cost me $110 for one (234-5117). As always, the invaluable help of the experts on this board can hopefully point me in the right direction before I spend several more hundred dollars to replace all 4 sensors

PKN

Also dont forget that you lose anbout 15% of power through the drive train on a two wheel drive car so the loss might be more on AWD. You are still way down though. It might be worth driving around for a few days with PSM turned off to get the ECU trained to a richer mixture Make sure AC is turned off and that you are running the highest octane gas you can get before the next run.

This is an interesting topic - maybe we can get a few others to contribute dyno numbers....

PKN

It is a devil of a place top put a connector. I busted mine when I was changing the air filters. I epoxied over the hole the connector left in the airbox and drilled/tapped a hole for a brass barbed connector and replaced the end of the plastic pipe with rubber vacuum tubing. I did the same with the one on the back of the inlet manifold when I changed the coolant pipes. Those plastic connectors go on easily enough, but they are a bugger to remove after a few thousand miles of engine heat cycles.

Incidentally, I changed all of the T connectors I could find with brass equivalents including the one under the inlake by the fan, the vacuum T behind the manifold on the bulkhead and the infamous coolant T pipes. Brass wont break but the car is a little heavier....

Steve

post cat is a seperate parameter and the Durametric (V6) describes these as just left bank and right bank so I guess they are pre-cat. the 0.6V reading fluctuates slightly but the 0.06 reading is static which is what drew my attantion to it. I might just swap them all out as my car is close to 100,000 miles. Are they all accessible from under the vehicle?

Steve

2006 TT and when playing with my Durametric, found that one bank is reading 0.6V output on the o2 sensor and the other bank is reading 0.06V. This is on a warm motor at idle after a long drive. I understand that the voltage fluctuates according to fuel mixture but a fairly stable 10:1 ratio between the banks seems odd. Can anybody comment on what readings they have and if this is normal?

Steve

I finally got around to looking for the reason for my CEL illumination. (numerous error codes but always fast idle on both banks)

My first find was a broken vacuum line connector from the passenger side air filter box. My solution there was to epoxy the hole in the air filter box and to thread a new hole to insert a brass barbed connector with some rubber vacuum hose. The original connector is easy to damage when changing air filters. I wasnt convinced that this was the cause of my problem which had recently been causing a rough idle and hesitation on accelerating.

There is a rubber "T" vacuum connector under the manifold intake and directly behind the fan. I discovered the T had split and that sometime in the past, the fan had nibbled away at a plastic elbow fitting. A quick run to Lowes plumbing departrment provided a brass T piece and elbow along with new stainless hose clamps. It took about an hour and $10 to effect this repair, codes cleared and she runs perfectly again. I found one other case of this problem ocurring on this forum but if you get a CEL and rough idle - check this first. It is easy to get to and easy to replace.

If you remove your intake manifold, take care that this rubber T piece is properly secured in the plastic clamp that keeps it away from the fan. I should say that in my case, the rubber piece had perished and not been slashed by the fan

Steve

I had a similar problem after leaking coolant down the engine block. It seems some of it got into the gear shift mechanism on the side of the transmission. I hosed down with water and left it a couple of days to dry out and it was fine.

I have also had a problem after a nickel managed to get inside the shifter.

Good luck with this

Steve

The same thing happened to me. I saw it coming because so many other on this forum said to change the Ts at the same time as the main coolant pipes but because the main pipes were actually in very good condition I thought I would be OK. 3 months or so later the infamous T broke and I dumped my coolant.

It is doable if you are handy but the job took me a weekend to do. Like others, I replaced one of the Ts with brass but used the replacement plastic Porsche part for the one that breaks. I have to say that using any plastic piping under the hood of this car was a stupid design failure. It just gets too hot under there for any of them to survive for too long and most are so inaccessible the design fault is compounded. I have already replaced aslmost every plastic coolant part including the coolant tank and vacuum line with the sad knowledge that sometime in the future, some poor sould will need to replace them again because with the exception of the metal replacements, they still have the same designed in obsolescence.

I am sorry for the expense you have to make again so soon. I hope you have a good independant dealer who can make it less painful for you. Sorry for the rant but I had to get it off my chest....

Steve