rjt86

I did torque then down correctly as I had access to the workshop manual at the time, however having said that it's been to a Porsche Indy who had to remove and refit the plugs to do the leak down test. Still the same issue unfortunately.

I'll have to test the coil wires more closely now as it seems the issue is not a simple one. I'll try dig up a wiring diagram to see what wire is doing what. Thanks for the point on the MAF sensors I didn't realise they are not important at idle. The shop I took it to did test these out and didn't find any faults with it.

Thanks for that fuel pumps were tested and pressure checked to ensure it's getting what it should be. Interesting point about the cylinder grouping, earth points were checked and new ones run for testing. I think I'll need durametric to check the airflow sensors but the shop tested it

Is there any other suggestions on what to look at that hasn't already been checked? Durametric won't give me any additional info that the shops have already seen, so I'm not feeling to confident even if I did have it.

Thanks for that however I purchased brand new coil packs from pelican parts along with new plugs, the old and new coils were tested with a coil tester and they all still work. The car not throwing camshaft deviation faults is the strange one, however I don't have durametric I'm using VCDS which works with this ecu to read faults as it's the same used on some VW's. I've purchased durametric and awaiting its arrival. However the workshops are Porsche specialists and they checked the specifics but couldn't pin point it for sure, other then one thinking it's the variocam adjuster, even in this case I would suspect a camshaft deviation code.

Sure, sorry i forgot to add them, the only fault codes i'm getting are as follows which were from a few weeks ago, i cleared them and will have to recheck for codes later today: Random/Multiple Cylinder Misfire Detected - P0300 - 002 - Intermittent Cylinder 8 P0308 - 002 - Misfire Detected - Intermittent Cylinder 7 P0307 - 002 - Misfire Detected - Intermittent Cylinder 6 P0306 - 002 - Misfire Detected - Intermittent Cylinder 5 P0305 - 002 - Misfire Detected - Intermittent

Hey Guys, Desperately seeking your help and knowledge on this one. I have a 2003 Cayenne turbo, the car is running very rough on idle also while driving if your gentle with the throttle it's ok, but when accelerated harder it hesitates and sounds like theres a backfire through the intake. After about 5k rpm it settles down and pulls hard. what i am seeing is multiple random misfire codes from cylinders 5,6,7,8 so it's only from the one bank. This is the only code thrown, absolutely nothing else. I've been to 2 Porsche independents who have both had a look but nothing concrete. One seemed to think its the variocam adjusters or variable cam timing for that one bank. The thing is i applied voltage to the actuator/solenoid and it adjusted the timing and the car ran rough while voltage was applied, this was the same effect on both banks. Seems to me that the variiocam adjusters and the solenoid is working? The following has been done: Compression & Leak down test checked fuses between the windscreen and engine bay Checked battery and fuses in that area Checked earth points under the bonnet and battery area Checked fuel pressure Swapped injectors from a good cylinder to a misfiring one and the problem did not follow installed 8 Brand new plugs and coils. Old coils tested OK anyway with a coil tester Smoke tested the intake system, there were some small leaks which have been fixed Applied voltage to the cam adjuster solenoids, both seemed to advance timing and the engine speed was reduced while voltage was applied. (same effect on both banks) Me and a mechanic friend will be checking timing by pulling the valve covers off, thats the only thing we have not done just yet. Any advice is appreciated as I'm coming to a loss of ideas.......Thank you!