Porsche Cayenne S 2005 CEL Floating RPM

[Kamil Barański]

Hi All,

Just joined Your group and hope to share some experience with the Cayenne S, many thanks in advance for helping me out.

Is just bought US version of 2005 Cayenne S and recently had some issues with the car. It first started with the starter which needed replacing. After that just after i got my car back a CEL showed up. At this moment i only know the error description not the code. It says that the car had problems with poor mixture of fuel and air and therefore the RPM goes little bit wild up to 1200 RPM. I keep on wondering if that is someway connected to the job that was done - starter replacement? The RPM floats only when I am on N,D or try to park not pushing the gas pedal. I will surely try to get some codes this Saturday, when having my oil and filter changed.

I sincerely doubt that it would be a gas cap as It came up after i picked the car from the repair shop.

Any ideas what the cause might be? The light is solid and doesn't blink.

[JFP in PA]

Without the code(s) number(s), anything would be a pure guess. Get it scanned, let us know the code(s).

[Kamil Barański]

Sure thing, I will. I was hoping that the description would guide a little bit to the cause of the problem. I remember it right that my friend told the code description. It was in polish :) so the only thing can do with it is to try translating it. He said that that "pure mixture" and car started adding RPM to about 1.200 and decreasing to a normal level.

Can' t wait do give some decent info about the codes.

[Scarpoolla]

The starter is located in the valley of the engine which also happens to be where the two knock sensors are located. I know from experience that if you damage the wiring or connectors to one of those knock sensors you will have all sorts of problems with fuel/aire mixture and the engine running rough and idling Like crap. If the knock sensors are damage, the car should throw a code for it.

[jagman1]

To replace the starter, the intake manifold is removed along with several vacuum lines and sensors. It's likely that they missed something, or damaged something in replacing the starter.

[Kamil Barański]

Hi

Many thanks for your replies. I am not excluding all possibilities. I refuled my car with a 98 octane gas, checked the gas cap. Light is still on. I don't feel anything strange when driving, speeding etc. But wojen i stop the rpm floats between 800-1000. I thought that the fuel i got lasy time was bad i guess it wasn't the root of the problem. I will let You know tomorrow about those codes.

What sensors are undertaker the intake? Whar are those 8 little blue Tunezja/ chips on both sides? Can the oxygen sensor give errors due to the błąd fuel? Last time i filled the gad tank with a 95 octane.

[Kamil Barański]

Sorry Guys for some errors in the above post, I am driving a highway and writing, not looking to much how the Iphone corrects some words.

Again, many thanks for Your input.

[wvicary]

Have the garage go over all connections and make sure nothing was left off and all electrical connections fully seated. Post the faults codes when you have them.

[Kamil Barański]

Hi Guys I have all codes now: P0507 Passive, P2177, P2189, P2179, P2187 all are active... Apparently there is a leak in the intake? Unwelcomed air goes to the intake system?

[Kamil Barański]

Hi Guys I have all codes now: P0507 Passive, P2177, P2189, P2179, P2187 all are active... Apparently there is a leak in the intake? Unwelcomed air goes to the intake system?

[Loren]

P0507 Idle Air Control at Stop - Above Limit

Possible cause of fault- Leaks in intake air system- Leaks in crankcase ventilation- Throttle adjusting unit faulty

P2177 Oxygen Sensing Adaptation, Lower Load Range, Bank 1 (FRAU1) – Above Limit

P2179 Oxygen Sensing Adaptation, Lower Load Range, Bank 2 (FRAU2) - Above Limit

P2187 Oxygen Sensing Adaptation, Idle Range, Bank 1 (RKAT1) - Above Limit

P2189 Oxygen Sensing Adaptation, Idle Range, Bank 2 (RKAT2) - Above Limit

Possible fault cause- Incorrect main charge signal- Intake air system leaking- Fuel pressure too low- Volume supply of fuel pump too low- Mechanical fault in injection valves- PCV valve leaks- Cap of oil filler neck leaking- Leaks in exhaust system- EVAP canister purge valve mechanically faulty (hangs open)- EVAP canister purge valve output stage faults

[Kamil Barański]

Hi Loren

Hello Everybody

I spoke to an engineer from porsche this morning when i exchanged the oil and filters. He said that that PVC valves are in terrible condition. He said that i should start from replacing all of them to new ones.

let me ask one question: can the airflow be a couse of this problem? I know that it didn't come up as a error code but should i exlude it from equation?

I think that there is also something wrong with one of the PVC valves as the longest should consist of two cables and in my case it seems that there is only one - the other one is not connected to anything (based on the drawing I got from Porsche)

I speak of this one: http://www.carpartsdiscount.com/auto/parts/2005/porsche/cayenne/pcv_system/engine_crankcase_breather_hose.html?3593=344513

What is its purpose?

I am not saying that I found the core of the issue but I will replace all of those hoses.

Cna it be the gasket under the intake? When the starter was replaced I was told that its ok and there is no need to have new

ones. Juged on time i would be better to have them replaced.

Can the mechanical fault in injection valves be connected with the starter replacement? Are those the 8 little blue chips i have on both sides of the black plastic intake?

Another question about the exhaust... I assume that the error should be before the lamda sensor (oxygen)?

Oh..I remember that Guys from Porsche said that its rather a problem with the air leak as it shows up on both sides of the engine. I

No issues on misfiring etc.

Please let me know Your opinion on where to begin and with what.

Edited May 11, 2013 by Kamil Barański

[Kamil Barański]

Hello Guys, anything i wrote rings a bell?

[wvicary]

This is turning into a guessing game. Have the intake system smoke tested for leaks.

[Kamil Barański]

Sure thing wvicary.

I thnik that based on the status of the PCV valves i will start from replacing them. They are in a very bad shape.

Does anyone have those nice PDF's Porsche has for every code? i mean those guidebook how to proceed with each problem, whee to start and what to do.

[deilenberger]

Kamil,

First pull over to send the emails.. :) We don't want to lose you to an accident caused by trying to write an email while driving.

Then I'd take it back to the shop that did the starter replacement. As others have mentioned - the manifold must be removed (along with other intake system lines) to R&R the starter. It seems more than a coincidence that the bad idle - and codes for intake leaks - started after that job was done. They either installed something wrong (like the intake manifold gaskets - they reused them? I would replace them with new), or cracked one of the hard plastic air-lines, or left something disconnected causing your intake air leaks. The smoke test wvicary suggests (where smoke is pressurized into the intake manifold and you look to see where it's escaping) will show you what is leaking quickly. Don't get distracted by mention of PVC valves when chances are - the real cause was a poorly done job when the starter was replaced.

Diagnostics based on guesses and parts replacement can become quite expensive quite quickly.

Edited May 12, 2013 by deilenberger

[Kamil Barański]

Hi Deilenberger,

Yes the intake gasket was reused. Apparently it was in a good shape...in their opinion. They will be replaced this Thursday along with crankcase PCV valves - 2 of them. As speaking of those PCV valves the is one goes from one bank to the other, it has this little nose on one side. What is it? I speak of this part : 948 107 215 03. When I was looking on it in the internet I saw that some offer this PCV without it. Does it has a special role or something? Is it connected via that nose to something? I can't see it on those PORSCHE drawings.

Which part do You mean by saying: or cracked one of the hard plastic air-lines?

I am trying to do as much as I can in the garage and replace things which can be done by myself without special tools. Rest I will leave to those Guys how made me worrying about my little P(!)G.

Many thanks for all Your help.

[Kamil Barański]

A brief update;

i have replaced crankcase ventilation tubes as they were cracked and connected the wrong way. It seems that the idle RPM are not fluctuating.

I went back to those guys who replaced the starter and thought that that was the case, the CEL was erased by them but after ca. 60 km came back. Wife says that when she switched off the engine it was on and when she came back and start the car after 9 hours it was on.

To bad that i am about 100 km from Porsche Dealer to check if the crankcase tubes solved the issue - partially at least.

Guys any ideas now?

[Kamil Barański]

Oh and another thing i need help with. When i fill the tank i always have an issue that i cannot fill it having the pistol pressed once and kept presed. it always pops up after 2-3 liters. any help what can cause this situation?

[JFP in PA]

A brief update; i have replaced crankcase ventilation tubes as they were cracked and connected the wrong way. It seems that the idle RPM are not fluctuating. I went back to those guys who replaced the starter and thought that that was the case, the CEL was erased by them but after ca. 60 km came back. Wife says that when she switched off the engine it was on and when she came back and start the car after 9 hours it was on. To bad that i am about 100 km from Porsche Dealer to check if the crankcase tubes solved the issue - partially at least. Guys any ideas now?

What codes this time?

[Kamil Barański]

Will know tomorrow morning, unfortunately it won't be porsche diagnosis tool. . .

[JFP in PA]

Will know tomorrow morning, unfortunately it won't be porsche diagnosis tool. . .

Depending upon what the code(s) is/are, that may be an issue as aftermarket OBD II cannot see some codes or misreport them. Check it with what you have.

[Kamil Barański]

Any suggestions what can cause the issue with proper tank filling? the same issue on different gas stations? Are those pistols different in US and Poland somehow:)?

[Kamil Barański]

Hi Guys, I have the code, itd P0455. Wouldn't that explain the issue with gad filling?? Where should I start now?

[JFP in PA]

Hi Guys, I have the code, itd P0455. Wouldn't that explain the issue with gad filling?? Where should I start now?

P0455 is a "large vacuum leak in the evaporative emissions system"; often a bad gas cap, but could also be vacuum lines or valve issues in the EVAP canister system.