buddy911t

I recently purchased a 997, black 35,000 mi beautiful shape, bringing it back to dealer third time for check engine light. They said it's probably deposits on intake and they did a cleaning process. It was fine for a week before the light came on again. Anyone have any experience with this?

997_rich

What was the code for the CEL? Misfires?

Very typically this can be cracked coils. Many people on the board have experinced that. It could also be bad gas etc.

Macster

Post the codes! Either insist the service department *write* them down when they're read (techs I know would do this, should do this without being told/asked) or buy your own code reader and read the codes yourself.

Take the car back and tell the dealer that you have lost all enjoyment from the car from this CEL business. You want the root cause id'd and fixed.

Remind the dealer that it is a Porsche dealer and should not have to guess as to what's wrong, but should know. After all it is supposed to have factory trained, experienced techs that should know these cars inside or out and as a backup have a phone line to PCNA/factory to get factory help for the truely puzzling problems.

With codes someone can point you to the areas of concern, but it will still require the dealer and its service department to fix what is wrong.

Sincerely,

Macster.

utkinpol

buddy911t

The dealership says they are in touch with Porsche about this. I'm trying not to be overly stressed about it at this time. The car still runs great, I just hope they get to the bottom of it this time. They gave me a brand new Audi a4 as a loaner last time, I requested the '86 cab. they have on their lot this time. If it has to go in again I want a GT3

McCulla

I won't bore you with details, but..my 05 had 3 CEL in 20 months, "random misfire" codes (0300 I think) that recently resulted in a replacement of all 24 lifters. Macster has a great rundown of possible causes, but if I remember right it includes tainted fuel, bad spark plugs, bad coil packs, fuel injector issues, vario cam actuators and solenoid issues, lifter (consequently valve train) functional variances, ignition issues, etc. Unfortunately the codes really don't give specific diagnostics and my tech had to go through all of these things. Ultimately, it resulted in the lifters being changed (about $5K-most of which was covered by my extended warranty). This can be tough to isolate. Sorry to be bearer of uncertainty, I hope yours is MUCH easier than mine has been. Good Luck!!

McCulla

Of course this issue that has occurred on my car is ONLY the "random misfire" code cause for CEL coming on. There are other reasons, and my situation may have no relation to your situation at all.

Macster

There is no reason to get stressed but you have to be firm and do not let the dealer just blow you off.

The car is not running right. The electronics has id'd this. The CEL is on. The owners manual says to take the car to the dealer for attention.

You did that. The dealer has not fullfilled its responsibility.

The dealer is a Porsche dealer. It owes you reasonable skill, experience, and care in servicing your vehicle. You are not getting that. The dealer can't just throw up its hands and give up and it can't/shouldn't just futz around and try things. The PST2/PIWIS and later this year, PIWIS2, provide a knowledgable/properly trained tech the tools he needs to diagnose the problem.

I was at one dealer a while back and asked about a tech was missing. I was told he was off at a week's training in southern CA specifically for OBD2 diagnostics. The dealer pays for this and IIRC it costs several thousand dollars. (I asked if I agreed to pay could I take the classes but was told the classes are for dealer employees only.)

Be sure when you are called to pick up the car, you take the car out for a 30 minute test drive *before* you sign paperwork and accept the car in case the CEL comes on again.

Be sure you collect copies of all service/work paperwork and be sure you list your complaints, how many times you've had the car in for this same problem, etc.

If the check engine light comes back on then you must leave the car and at the same time ask the dealer to escalate this to PCNA/the factory. You are tired of having the car in the shop for this.

Sincerely,

Macster.

sandwedge

What did they trace the CEL light to? Could be a number of things, some of which you wouldn't expect. I had it come on repeatedly and mine was for a sensor that detects a leak in the fuel tank. No leak....just a faulty sensor.

McCulla

As Macster says, the tech's software is the diagnostic gold standard. The tech at my shop let me watch the engine go through it's "malfunctions" in real time (engine running) while hooked up to the computer. I understand that not only is the training really pricey, the continual Porsche factory software upgrades to their diagnostic machinery are huge money.

Macster

One of the dealer service departments I visited recently told me its PIWIS system goes 'dark' later this month. The license expires and Porsche has not offered to extend the license.

The dealership service department, and I guess this is true of all of them, have to switch over to PIWIS2. I saw one and its nice, but the techs like the PIWIS device better. It is a bit easier to use, hook up, in short the techs prefer the older PIWIS to the newer PIWIS2.

Oh, God only knows what the PIWIS2 system cost.

Sincerely,

Macster.

utkinpol

it is bad news indeed, that means that most independent shops will also have to buy new piwis2 and then boost rates to pay it off. it sucks.

gpjli2

Buddy (OP) is this a .1 motor or a DFI (.2) version? Don't see this info and it would be important to know.

buddy911t

I believe it's a .1. How would you know for sure? It's an '05.
I was told by the dealer that the cel code is po-306 #6 misfire.


On another subject. I can't access forums from my home computer anymore. I've cleared cookies. Forums just won't load no matter what I try.Can access from any other, at work now. Anyone ever have this problem?

Macster

Can't help with the home computer issue...

As for the error code, that's a misfire on cyl. #6.

It could very well be 'valve deposits'. I'm pretty sure the engine is *not* a DFI engine, and the pre-DFI engines were not real prone to this problem, but it can still happen.

The pre-DFI engines inject fuel ahead of the intake valves and this tends to wash the valves clean.

Due to the way these engines work there is some flow of exhaust gases into the intake valve area and this can leave deposits (the hot exhaust gases leave deposits from contacting the colder intake valves) on the intake valves.

If these deposits do accumulate they can begin to interfere with the very critical air flow into the combustion chamber and this can lead to mild misfires.

An inspection of the intake side of the intake valves would be nice but rather labor intensive but it would confirm the presence of deposits.

You have to rely upon the dealer's experience/knowledge of these cars and engines.

Couple of things you can do. 1) Buy a name brand gasoline. Buy from a busy gas station to get the freshest gasoline. Of course use the right octane grade. 2) Use the engine a bit harder. No need to get mean with the car and the engine but try to use the engine at a slightly higher rpm range that I suspect you have been.

Low(er) speed operation will subject the engine to operating conditions that are more prone to the creation of intake valve deposits (actually deposits throughout the engine combustion/exhaust areas).

You can also run a bottle or two of Techron through the gas tank, following directions on the bottle.

When I use Techron -- I use some every couple of years prior to having one of my car's smog checked -- I like to then change the oil/filter after the last tank of Techron is down to under a quarter of a tank.

Be on your toes. If the misfires come back -- course you'll have to have a way to read the codes or rely on taking the car somewhere to have them read -- start appearing at other cylinders, or if the engine starts misbehaving in any way out of the ordinary, take the car in pronto.

Sometimes misfires are precursor to more serious engine troubles. You can't do anything about this if its going to happen, all you can do is be very quick to get the engine looked into as soon as possible to if the problem is more serious to limit the risk to the engine and your billfold.

Sincerely,

Macster.