mbagge01

I have an 04 CTT with an evoms tune and wanted to get opinions from the forum on recommendations of spark plugs for this tune, or any tune for that matter. Are stock plugs and stock gap fine or should gap be reduced for increased power or different plugs.

On my 2004 cayenne turbo, I have an EVOM intake along with other mods and an EVOM tune. I have been having issues with smooth delivery of acceleration and it has been suggested that it could be the EVOM intake causing turbulent flow and giving the MAF false readings. Any thoughts by those who have an aftermarket intake? Anything that can be done beyond replacing the stock intakes. I have checked all the other potential issues (ignition and fuel system, pressure test)

I have a question regarding the upgraded intercoolers on the market for the 955 cayenne turbo. Today my 2004 cayenne turbo got in an accident because of this crazy weather with the front end being damaged along with the right sided intercooler taking a hit. I have the FVD upgraded intercoolers on the car and am now going to have to find a replacement. Does anyone know if the FVD intecoolers are just the OEM intercoolers off the cayenne turbo S or are they a different design or size. If they are different, would I be able to just get an OEM turbo S intercooler to hook up to the piping that came with the FVD set. Also are there any metal replacements for the plastic intake pipes that go to the intake boot because mine on the right, off the intercooler, was also cracked in half during the accident.

I have a 2003 955 turbo with evoms tune and after sorting out all the gremlins, it drives great in tip mode but in regular automatic drive mode, the shifting patterns are annoying. Sometimes when I give it half acceleration it shifts up a gear and sometimes it will not drop down a gear under full acceleration. Have any improvements on the transmission module been made since the production of my car to make the shifting more sporty.

I am hoping that someone can help confirm the correct part numbers for the OEM porsche oils for the transmission and front/rear differential. I am finding some differences between the PET catalog and what is on the TSB here on this site. What i have concluded so far is that the front and rear differentials use OEM part number 00004320530 which are 1L bottles of 75W90 fluid. For the transmission I am finding on PET the part numbers 00004320528 and 00004330136 for 1L bottles. The differential part numbers seem to be correct but I am not sure about the transmission fluid part numbers.

The dash gauge works but as you know it is not really accurate and I would like a gauge to get an accurate reading of boost with my tune. I will probably try to find a way to connect near the intake manifold on the back near the firewall where the hoses are coming off

I am planning on installing a boost gauge and wanted advice from the forum on which line I should tap into to get the most accurate readings on my 04 ctt

Has anyone heard or have experienced problems with the fuel system (fuel pumps specifically) when having a bad battery. I came across some articles suggesting that there could be a relationship. I have been having issues with my timing getting pulled with my evom tune and I have been narrowing it down to possibly low fuel pressure. I replaced all the fuel system components with no improvement. I just replaced my battery today because I have been getting weird codes on durametric which per my research led towards a bad battery. Also when testing my battery, it was becoming weak at holding a charge. After replacing the battery, my driving issues seem to have gone away. I don't know if it was the ECU getting reset because of the battery being disconnected or better charge to the fuel pumps with the new battery. I would be interested in any thoughts of those on the forum.

It is a hidden radar install so a few wires need to be passed through the firewall to the front of the car.

Well, after about 3 hours of frustration, I was able to change out the precat O2 sensors on my 955 CTT without needing the special hazet tools. I am not sure if it is the same layout as the cayenne S but it is a challenge but doable. I only had the remove the engine bay covers and the lower splash pan to accomplish the job. The drivers side one took the longest and involved using some creativity and some different O2 sensor ratchets and angled attachments from above down into the engine bay. The use of an inspection camera helped alot. The passengers side was very easy compared to what I went through on the drivers side. You can actually reach the passengers side sensor with your hand by reaching up behind the wheel well from underneath the car. Once you get it loose, you can actually use your hand to remove it and put the new one in. Looking at where the post cat O2 sensors are, I do not think I could even get to them without at least removing the secondary cat pipes. I am not too concerned about the post cat O2 sensors unless I get a code because they do not affect the air/fuel mixtures like the pre cats. This project felt like when I changed out the drivers side diverter valve.

I am interested in installing a radar detector and was hoping someone may know where the firewall on a 955 CTT can be accessed to route wires into the cabin. Are there grommets on the firewall like on audi's that can be used to get through the firewall.

Hey Loren, if you have any installation info for replacing o2 sensors on a 955 cayenne turbo I would appreciate it. Looking in the engine bay, I can see the pre cat sensors and it almost looks as if I could get an o2 sensor wrench along with some angled ratchets to get to it from above but it does not look easy. I would like to replace them without having the engine dropped out to get to it.

Can someone tell me the significance of what high injector times means. I know that low fuel pressure can be one cause, but if the fuel pressure is fine, what else can lead to this and ultimately affecting performance or pulling timing.

I unfortunately broke my left one trying to get the MAF out. I ordered some new ones but was wondering if anyone makes silicone hose replacements for these parts

I wanted to ask the experts here if I have the correct understanding of the changeover/diverter valve system. In my 04 CTT I replaced the oem diverters with the evom diverters and assume that they function and are positioned the same way. Now for how I understand the system. The top of the changeover valve receives a connection from the intake manifold and gets a vacumn signal at idle or boost at acceleration. This pressure signal then travels through the perpendicular port from the top inlet port and ends up by hoses, connected to the nipples on each diverter valve. I am not sure yet where the parallel port at the bottom of the changeover valve ends up. If the signal on the diverter valve is vacumn at idle, the spring is open and air circulates from the perpendicular port to the bottom parrallel port. At acceleration, boost is applied at the nipples on the diverters as well as boost going through the perpendicular point from the intake to keep the diverter closed. Once shifting occurs or boost is released, air then circulates from the pressurized perpendicular port down through the parrallel port back to the cold side of the turbo. I am not sure either in what situations the computer manipulates the changeover valve to open or close the diverter under different situations. Does anyone know if the memory kink in the diverter hose on the passenger side can cause a problem. Also could a bad diverter valve closing properly cause hesistation during acceleration. I have read of people putting their diverter valves on backwards as well and not sure of the ramifications of this.

On inspecting on how to car drives some more, I think it has something to do with the way the boost comes on. If I am around 2-3k and give it WOT, the boost gauge shoots up and it does the weird surging issue. If I give it part throttle to get the boost to around 0.4 first and then give it WOT, I don't seem to get the problem as much when the boost pressure raises. If I hit WOT at around 4500-5000k, I don't seem to have the problems either. I already have a new boost solenoid valve and MAP valve and I am wondering if I should change out my changeover valve. Could it be possible that I am having boost spikes or my boost is raising to fast due to the changeover valve not opening properly causing the diverters to open erratically, affecting boost control?

I just wanted to add that I decided to regap the plugs to .025 inch and the first run with the car was perfect but after it warms up, that is when the problems start up. I am now starting to wonder if it could be something like the O2 sensors going bad and giving bad signals when they heat up. Has anyone had any problems with the O2 sensors doing funny things, even though a code has not popped up yet. What are the O2 signal values that are normal in durametric.

I am hoping that the collective knowledge of this forum could help answer the problem I am having. It involves a 63000 mile 2004 CTT with evom tune, evom intake, upgraded intercoolers, ipd plenum, new fuel pumps, fuel filter, and FPR and new boost solenoid. I have no CEL on durametric. My car pegs the boost gauge which is what should happen with the evom tune so I am assuming that I do not have a boost leak. My issue is that the car feels more powerful at half throttle than at WOT. It is a very rare occasion that I can hit WOT and the car pulls like a freight train but this usual only happens right after the car is started. I have tried 4 different types of spark plugs and currently using denso pk20tt which evom suggested. It came with a gap of .033 inches and I know that this is smaller than the porsche recommended gap but my understanding is that creating a smaller gap is good when a vehicle is tuned for more boost. Regular driving is fine but if I ever give it hard throttle, the boost gauge goes up but the acceleration feels very slow, and even as if the timing is being pulled for some reason. Could my boost solenoid not be reacting fast enough, could my changeover solenoid be acting funny, should I reduce the gap of my spark plugs even more. I am probably going to log some runs with durametric to see if I can get anymore insight into what it could be. Appreciate any advice on what else I should try or look for.

hahnmgh63, don't worry about it. I figured out my problem. first off I found out the one of the hoses had ripped which was part of the problem, I a also misread PET about the connections and had some of the hoses backwards. Fixing these issues seemed to fix the problem. Thanks though.

Does anyone have a diagram of what hoses connect to which pipe ends off the boost control solenoid

I just replaced my wastegate frequency valve (the solenoid behind the left SAI box) and I am now getting the underboost error on durametric and cannot achieve boost over 0.4bar anymore. Does someone have a diagram of which hoses connect to which end in case I may have installed it incorrectly. I am guessing that I should do a boost leak test to make sure that none of the other lines cracked or broke causing a leak when I installed it?

I just looked up my TCM SW version on my cayenne turbo, and it is 0351 which is the original version. I do have an EVOM tune on the car and wondering if I should look into getting the TCM updated, if this would improve transmission shift changes. Does updating the DME with a tune change the SW number as durametric tells me that it is 0135. I have read the TSB regarding the TCM change and my DME SW version is not one that also requires a DME update to change the TCM if I understand it correctly.

I just replaced my tpms sensors with aftermarket orotek ones from ebay for $45 a piece and they work perfectly.

My other question would be, can I use aftermarket 433mhz sensors (like to ones on ebay) that say they are compatible with the porsche system.

I have a 2003 CTT which I bought used and I think that the batteries in the wheel sensors have all died. I am trying to determine the appropriate part numbers and what the original part number for the sensors is 95536166100 in PET but it appears that there is an updated part number as 95536166101. Are both of these sensors the same frequency of 433mhz. If I go with the new model number sensors, do I also need to change to the newer model number antenna in the wheel well. The old number is 95564711100 and the new one is 95564711101. Or will the new sensors work with my older antenna? Thanks.