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By Graeme Tate
I hate my pig but I love my pig, can anyone please help me before I send it for scrap. Over the space of the last 4 years of ownership my car has been in the Porsche dealers for 2 years in total with suspension problems, to cut a long story short this is now sorted and was due to a faulty replacement air bag being fitted. Moving on after 3 months of (almost) trouble free motoring this is what’s happening now and would love some advice as the closest porsche dealers is over 200 miles away from me.
When I picked up the car from Porsche it ran out of petrol before I got to the garage at the end of the road and although I filled it up it the engine warning light remained on I assumed this was just fuel related and drove home with it on and reset it when I got home.
Wind on a few weeks and the engine light came back on and gave me a camshaft position sensor error p0016 so I sent the car to my local Porsche mechanic who changed out the sensor and did a full service on the car including plugs filter oil etc etc. All this time the car has been running fine but as I wanted the sensor light out it was changed. However after changing it out the light came back on almost straight away. The car has been a bit sluggish to start sometimes and sometimes on pulling away from a stop has also been hesitant.
This was about 3-4 weeks ago and now it is worse again, at tickover it’s noisy, it doesn’t like acceleration and is running really rough although if you are going over 50mph it doesn’t have a problem and seems to run fine. The EML is now flashing rather than being a solid light. I attach a video of it running.
Any thoughts would be a help before I decide to get it hauled back across again
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My 2005 Cayenne (190k miles) had been misfiring and running rough. I’ve replaced the plugs and coils, which cleared numerous misfire codes. It starts and idles fine, but at around 3500 rpm, it labors to shift, chokes or runs rough, and occasionally dies completely. Durametic gives codes p0335-p0337. So, my question is, does anyone have detailed instructions (a video link would be awesome!) for replacing a CPS? I have the service manual instructions, but have to admit they aren’t very instructive and the pictures are really “uninspired”. I ordered a new CPS from Amazon, but sure can’t find anything under the hood that looks like it. Help!
By Schnell Gelb
2001 Boxster S 6 speed, 3.2L, 92,000 miles - engine recently rebuilt with many ,many new parts. Ran well.It passed Smog then a few weeks/hundred miles later started developing P0300 misfire codes for all 3 cylinders on Bank 1.
A few lifters were ticking and the engine barely ran , so I replaced all 24 lifters . Now it will not start and is over fueling. There is raw gas in the headers !
When I removed the Cams to replace the Lifters, I also found raw fuel in both headers. I assumed this was a symptom of Misfire caused by some collapsed lifters.
There is plenty of fuel flow at the Test Port.
The Crankshaft Position Sensor is new(for Smog Test) & the tachometer bounces when I crank the engine.All the dash warning lights illuminate correctly during cranking so I 'guess' the Ignition switch is O.K.
The battery is new and tests perfectly.
The camshafts rotate when the engine is cranked(remove green plugs) .
The IMS sprocket was pinned to the shaft during the engine rebuild.
I haven't checked compression but when I rotate it by hand on the crankshaft bolt(to check timing) it seems normal.
All 6 coils and plugs are new and the car had these when it passed Smog recently.
The SAI system was fixed prior to the Smog Test.
I have not checked/replaced the camshaft position sensor. They seldom seem to fail.
When the Bank 1 camshafts were off the engine I confirmed the 'window' for the camshaft position sensor was not bent nor loose.
I can check to see if there is a complete blockage of the inlet system. I mention this because I did replace the Airbox with a CAI prior to the Smog Test and it ran well.
I have checked many times that I reconnected (after replacing the Lifters) all the connectors for the Variocam solenoids, O2 sensors, oil pressure sensor, camshaft sensor,crankshaft position sensor.
The car sat for around 2 months while I did the Lifter work. The Ignition key remained on the dash but not in the ignition switch throughout this period.
The car was in a garage so the immobilizer did not get wet and has never been wet.
The new battery remained fully charged throughout. I did do the Initialization procedure when I tried to start it but only after building oil pressure(remove fuel pump fuse C4).
* Is there some technique with Durametric during cranking to help pinpoint the problem ? In the past, I have only used Durametric with the engine running.There are no codes yet because the engine will not start. There must be some Freeze Frame that would show a total failure of the Ignition system?
What am I missing ? DME checks?
Any helpful suggestions would be most gratefully received.
As I lurk all the time, I thought I'd post what I have going on for the benefit of anyone that can use it. Lately I've been having the dreaded intermittent cranks but won't start situation. It seems to occur mostly when the engine is warm. If left for an hour it starts up. It happens twice in a day, or not for 3 weeks, totally random. The car runs fine when its running. It's only stalled once while running. I was idling in the parking lot. Just as I noticed rpms swinging between about 780 and 730ishm dead. Started an hour later.
I tried a fully charged, brand new battery one time during the no start condition and it did not help
New fuel relay, no help.
A DME Relay is on the way. I won't install it for a while to verify if it was the Crankshaft Position Sensor.
Today I changed out the Crankshaft Position Sensor. The old one was covered in gunk and the magnetic tip was black. The new one, nice and shiny magnet there. So far so good, I'll update in a week or two.
The CPS is indeed a pretty easy job, anyone can do. Just don't drop the screw in there anywhere! I stuck some chewing gum in it, smushed it onto the allen socket and gently got it started. Removing it, was the same. Slow and gentle. I used an allen socket and 1 long and one 6 inch extension put together. Reaches in no problem.
I've attached a couple of pictures to help locate it. Looking from the drivers side through the wheel well you can see it as shown by the red arrow picture. Thats just the hole after its been removed. I forgot to get a shot of it in there The Yellow arrow picture shows its appearance if you were to slide under the car from behind, head first and just to the inside of the drivers side wheel well. I've outlined the wire and labeled the CPS B (from the red picture) and the plug end "A". The plug has a little lever tab on top that you can't see, Feel for it and push it down to disengage the plug. You can totally get at it if you contort properly, no big deal. That black plug to the left of it is something else and it made life easier to pull it out of its clip. Pretty sure it just pulled straight out.
Anyway, for what its worth. Fingers crossed its the CPS or the DME Relay next. If not, I'm headed towards fuel pump I suppose....
I'm troubleshooting an issue with random rough running values below 2.0, infrequent and random hot re-start idle stumble (difficulty holding 680rpm momentarily), and stalls once or twice after hot and idling.
I've already located the specs for the crank sender and ohmed mine out at 839 at 50F, which I understand is within spec of 800-1000 ohms, however closer to the "tired side" as I've read people with new sensors have read closer to 950 ohms. I plan to artificially heat the sensor and re-test.
I'm hoping it's not an issue with the DMF, but want to also rule out the cam senders as well. I think I will replace the crank position sensor regardless, since it is a $100 or so part and easy to get to.
I can't find any specs on what the cam position sensors should ohm out at or which pins to test.
Thanks in advance if someone has those specs.
(no codes of course). ;)