Hi All,

I am battling fuel pump (I believe) issues. I ahve replaced the pumps int he tank as well as the filter and sending unit. All coils and plugs have been replaced and one injector was bad (P0203 code).

In any case I am still suffering form the "slump band" in the RPM range while under load (driving). GTS is a 6 speed manual so it's very easy to put the vehicle in the slump.

I hooked it up to the Durametric this morning and took it for a drive. I utilized the logging feature and initiated the following:

1) Fuel Level (53)
2) Pressure Upstream of Throttle Body (902.7 mBar)
3) Fuel High Pressure Set Point (40 BAR)
4) Fuel High PRessure Acutal Value (40 BAR)

Problem is I'm unsure of what the factory spec is for mBAR and BAR pressures. If anyone can let me know it would be greatly appreciated!

 

did you check the injectors?

 

Hi aspenone,

I'm just in process of taking the covers off of the engine now. I believe that the injector on cylinder three is bad according to the codes. May not be the injector itself as the code shows "open circuit" so may be a bad connection. In any case I will meter it out to see if there is a signal or not.
This is my first Porsche but definitely not my first German car (mostly been Audi, VW and one BMW). I have tkaen the bank 1-4 cover off (passenger side of engine) and the injectors aren't normally where the VAG group has them. From first looks it appears the entire intake plenum has to be removed?
Just to clarify the local Porsche dealer changed the injectors about 6K miles ago, previous owner.

I've done a search and can't seem to find any DIY for removing / testing / installing the injectors.

 

Hi brother
Sounds as though the injector might be faulty if its intermitant basically sounds like the injector is getting power and then not causing most likely a missfire since that cylinder wont be firing. How long ago as far as months did they change them? Might still be under warranty. As far as the location Im not sure where they are Ive never had to take it apart. I would search Rennasiance mans post about changing his intake plenum when he upgraded which the TURBO S has. He provided pictures of the install with the intake plenum off which should give you a better idea. If that is the case I would order the intake gaskets first before removing it since they will need to be replaced.

 

Thanks Aspenone, indeed I believe it is a faulty injector. I'm not sure if I should replace all of the injectors, I may as well since I have the intake manifold removed already... no use doing the same thing twice but...

I perused RennaisanceMan's pages, man, my jaw muscles are sore as my mouth was agape, RM's Cayenne is really something else! RM, if you do happen to read this well done! Unfortunately I am NA for now unitl VF or somebody builds a plenum mounted SC. Then I will be first in line. Next things for the CGTS is the front cat delete pipes and the CAI system. Not much other than that to do right now. RM, if you do chime in do you think if I am going to the cat delete and the CAI system I should maybe look at the next size up injectors?

I'm going to replace the HPFP anyway as it really seems to be easier to replace with the intake removed. I didn't order the gaskets yet but I did ask the dealership here in Calgary if they had them in stock and voila, they do!

So, any opinions if I should replace all of the injectors or just Cylinder #3 as that is the only one showing a fault? Oh yeah, real fun disconnecting the electrical off of the back of the intake. This motor is NOT made for a rugby players hands hahaha!