theanalyst

Hi guys, so glad I found this place to try and get some help with my 07 997tt problems

I am UK based and recently bought a 997.1 tt that has some running issues.... I have taken it back from the garage who was fixing it and am going to sort it myself back in my own garage. I have done a lot of work on my other cars, supra engine builds, m3 builds, kit cars, but I have very little flat 6 experience up to now... but that is going to change lol

A brief summary, car idled roughly and seemed to be down on boost on a small test drive, so it has had all the exhausts off, new studs and nuts , front rad pipes etc
Now, on test drive it was making a noise from the OS (rhd car) turbo (whooshing) was down on boost and 'get up and go' and when the tech got it back to the garage he blipped the throttle and it was throwing some fuelly smelling smoke out of the OS exhaust when blipped.
We have found the turbo is blowing (corrosion it seems) between cold and hotside on the OS turbo, also evidence of soot marks in there. NS turbo has a micro soot mark evident but is not yet blowing clearly.
So I have taken the car home, before the bill gets too terrible and am fixing it myself. hoping for some help from the good guys on here!!

I am going to get the turbos removed next week, and then either repaired or replaced, the car idles and revs beautifully from startup, its seemed to be when hot that this issue became more apparent. Engine always sounds like a sweet mezger, so I am hopeful it is the turbo issue that is causing over fuelling and erratic idle at times. It isnt misfiring. Would be really grateful for any wisdom from 997t guys before i start to travel this path! (and during!)


Cliff notes//
cars runs nice
more erratic idle when up to temp]
after hard run, turbo whoosh, missing boost, OS tailpipe put smoke puff out when revved hard at idle.
OS turbo is leaking exhaust gas
NS turbo looks to have a micro leak, maybe from when very hot
80k miles car, has been maintained well looking at history


MANY THANKS IN ADVANCE

Kevin

Read and Post the CEL codes?

MAF (two) failures?
Intake leaks?
Bypass valve leaks/failure?
Plugs?
Coilpacks?
Fuel pump failure one or two?
Fuel pressure?
Fuel filter?
O2 sensors "wideband failure?
VNT turbine housing LINKAGE failure?
Battery voltage too low due to failing alternator regulator or
Battery?
Compressor side sealing ring failure OIL present in intercoolers? Pull lower boost hose from turbo to Intercooler.

nzskater

Forgive my ignorance , what does OS and NS stand for?

theanalyst

Hi Kevin, thanks a lot for the reply!
ok, so I am driving the car back to my garage on tuesday so can supply more details then, but this is where its at right now.

Fault codes we read before doing the jobs on it

P1647 aux water pump driver
8004 terminal 50
steering angle sensor not calibrated

They replaced the aux water pump ;
The ignition switch needs replacing as sometimes it takes a jiggle of the key to turn the ignition on, I think that caused the terminal 50 code, I will replace it as have a new switch.
Steering angle is from when the bettery was flat after I parked the car up for a few weeks. We have fitted a new Bosch battery.


MAF (two) failures? - I havent checked them yet, but will do

Intake leaks? Not had it running for long enough to check yet, is there a boost leak test guide anywhere?

Bypass valve leaks/failure? on the turbos?

Plugs? Plugs and coils replaced 2 years ago according to receipts. Visual check shows them in good condition, new heatshield fitted
Coilpacks?
Fuel pump failure one or two? - Any info on how to check for this? I only have access to a snapon scanner currently, I couldnt find live data. I am thinking of buying an Icarsoft scanner which apparently can read live data etc. I would like a cloned Piwis but not found one yet

Fuel pressure? NO codes?
Fuel filter? Not checked yet

O2 sensors "wideband failure? - wouldnt this throw a code?
VNT turbine housing LINKAGE failure? Linkage visually attached, will check for free operation when removed
Battery voltage too low due to failing alternator regulator or
Battery? New battery, alternator chargeing
Compressor side sealing ring failure OIL present in intercoolers? Pull lower boost hose from turbo to Intercooler. - will check this as soon as I have the car back!!


THanks this is a great starting list

I did wonder if the Snapon scanner would read the same fault codes as a Piwis? I guess it should do. There is no warning lights on the dash.

Since getting the car I have discovered how little there is in the way of workshop manuals. This is most disappointing, if I was in the USA I could use Piwis online but it wont let me pay with a uk address credit card
I have managed to get the engine removal and build manual but nothing in the way of troubleshooting manuals....?

theanalyst

Sorry NS - Near side
OS = Offside

Not sure if its the same in the US but NS is the side nearest the curb which on a Drive on the left road is the left hand side of the car as you sit in it. The right side of the car being the OS

Kevin

Food for thought. With the PIWIS 3 out in shops. Good PIWIS 2's are up for sale. I will be selling mine later this year once I am fully comfortable with the PIWIS 3..
For the DIYer getting a PIWIS will make life a lot easier..

theanalyst

Thanks Kevin.
I so wish I lived near your shop and the car would be there for a diagnosis !!!

I may have to get the durametric for now. It looks like it pulls the Porsche specific fault codes which is something I think is vital over the OBD generic ones that the snapon gives (pretty useless).

Do you think it could just be the faulty turbo causing the RHS (USA passenger side) exhaust to smoke when the car is hot and then the throttle is blipped. I will know a lot more once I have the car. I just dont know why it doesnt do it when its on startup or until the car is hot, my hope is that the hot side turbo is also leaking a bit of oil and its a fuelly (slightly oilly) oil smell when the car is revved, just on the overrun part after you have let off the accelerator. I think my first course of action has to be to replace both turbos, and run ideally a piwis (I dont have) or a durametric scan after that.

Feeling a bit stressed (saying it lightly) with it at the minute!! Thanks!

theanalyst

I was thinking if when the turbo starts blowing, the post cat lambda will be reading as lean, and the ecu is adding more fuel to compensate, but I may well be being hopeful here lol

theanalyst

As an update to this I now have the car home and have driven it properly on the way back from the garage. The engine runs sweetly and is very quiet, however the RHS (uk drivers side ) turbo is clearly not healthy and is causing boost issues and blowing oil past its seal. I bought Durametric as a stop gap until I can get a PIWIS 2, and it has proven to be far more useful than I expected.

The faults I found when I drove the car was (lack of boost, not running smoothly or as fast as it should be) and a nasty loud pop/clunk from the front end seemingly over certain types of potholes, but I need more time in the car with it driving right to sort that.

The fault codes I have found are

P0238 - turbocharger boost sensor circuit high

PO112 - Intake air temperature sensor 1 circuit flow


At idle and when revved statically the live data didnt show any misfires etc and nor were any codes reported.


So if its of any use to anyone I will do some updates on removing the turbos, getting them rebuilt or replaced and the rebuild. I am going to go through it all, do a boost leak check, check vac lines and so on and get it back together and see where I am at... I found a place here that has developed a repair kit for the turbos, where they machine out the housing, weld in a machined plate and then a stainless steel side cover to protect the turbo from future rust.

While I am quite p*ssed off with having these troubles I am also still happy to have the car and don't mind working on it with the end goal of getting it on the roads for the Summer time hopefully...!!!

I will test the air intake sensor when I get the car on stands next week to get the turbos off.. Any DIYs on turbo removal by any chance?

cheers

theanalyst

Also, a loud bang noise from the front over certain types of bump, I suspect an issue with the NS (US drivers side) front damper as I noticed it didnt look right on visual inspection (could be wrong, need to check more), is this the same damper as found on a 997 carrera 4 with sport mode, does anyone know? or what are the options in case I need to replace it. thanks

Mike Billings

Regarding the codes you posted, I believe the sensor that is mounted on the Y-pipe contains both the boost sensor and temp sensor.

Is that sensor plugged in?

The terminology you listed "circuit high" and "circuit flow" seems to refer to a sensor possibly not plugged in.

rabbitstew

Clunk may well be top mounts on the shocks, very common problem. If you are near Centre Gravity then id highly recommend visiting them. They can give your suspension a complete check over.

theanalyst

Thanks Mike, Will have a dig round tonight and see what I can find and post back.

theanalyst

Good point, it sounded more central to the car but it could be deceiving! Makes a real bang over a bump? If its top mounts I will be more than happy at that !! will check them when its in the garage

RLR997

Any update on the sensor issues? I just bought a 997TT and now its delivered I have no boost and a P0238 error. Could the MAF sensor be the issue?