I have a friend who purchased a 993 Cab 3 months ago (1996 built I believe). The check engine light kept coming on...Local shop could not diag it properly.

Took it to the dealership and bad news: Carbon in engine and leak.

Total: over $7K to fix the problem.

Here is what is needed:

- Descarbonization
- New Gaskets
- Take engine apart

Parts total is about $1,700 but they need over 50 hours labor to do the job. Does this seem correct to you? They also said they need over 16 hours to change the clutch!!!

Sorry for my ignorance but it does seem a little overboard to me....

Any info, thoughts appreciated.

Thank you.

 

I am thinking about purchasing a 98 C2S and but with this scary information. I am now on the fence in purchasing the car. My question is:

How do you avoid having these problems?

When buying a 80K+ car new shouldn't it be close to perfect, with parts that don't go bad after 40-60K miles?

I am a novice in this whole Porsche thing.

 

I'm pretty new to the Porsche thing as well and therefore no expert but carbon build up in the air injection pump is a pretty common thing. Expensive to repair as well since I think the only real solution is to pull the engine apart - you can try to clean the carbon without pulling the motor apart but I don't think that's a long term solution.

I believe the build up is the result of ******* the engine at too low an RPM for extended periods of time. I can't help you out on the estimated costs but I do know it's a big job.

Good luck and sorry for your friend's misfortune.

 

There are alternatives. The Carbon buildup has been discussed here extensively, lately there was a solution posted to disable the sensor that sends the signal. You see MY1995 993's did not have the OBDII but the simpler OBDI which as suspected does not register any faults like that , therefore even though 95's may actually have the exact same problem noone knows about this, hence engines are not been pulled apart to fix it, which means that it is not a fatal problem.
I would suggest your friend to do an archive search on the matter, there is a ton of info on this and watch this post for any other info.
Also i would suggest to contact our tech guru here Steve Weiner from Rennsportsystems in Portland who has often offered his expert views on the matter.

Like tech-law said our engines need from time to time an "italian rune-up" and the occassional tank of techron which is suspected to at least prevent the build-up. An excursion to your local track is what the doctor ordered for a 993 engine.

Good luck.

 

Your friend should consult with others before spending the money. Steve Weiner at Rennsport Systems is a good first step.

The check engine light can come on for something as stupid as a poorly sealed gas cap. A bad oxygen sensor (or sensors, there are two in the '96) can also cause it.

If it is due to carbon buildup, some folks have had good results using a fancy engine vacum that gets the carbon out.

Lots of much less expensive options to check first.

 

Re the quote in question. If the service is performed by a Porsche dealer the amount is not out of line. My quote was for ~74 hours at $125 per hour. I was lucky in that PCNA picked up the tab. I'm still not quite sure why... Just grateful.

Carbon build up IS a problem with these cars, though there are multiple ways to deal with it.

Cheers,
Chris

 

Lots of good info on this topic on the PCA website as well. See in particular this from PCA Tech Advisor Joel Reiser, which discusses costs and options:

<a href="http://www.pca.org/tech/tech_qa_question.asp?id={FD2D349A-21F5-407B-9DF7-3455055E677A}" target="_blank">http://www.pca.org/tech/tech_qa_question.asp?id={FD2D349A-21F5-407B-9DF7-3455055E677A}</a>

 

At first I thought sixteen hours for the clutch was too much, but after searching the archives I think it is about right.

The clutch needs replacing. The ODBII hit, on the other hand, I would seriously consider just faking it. The carbon build up "problem" doesn't effect engine performance, reliability or longivity. It only effects tailpipe emissions during the first thirty seconds after startup. There is a work around that allows the OBD to be fooled for these first thirty (or so) seconds, then restores everything to proper operation.

It is still important to make the light go away (either by cleaning the carbon or "cleaning" the OBD), because you don't want the lame carbon check engine light to conceal a serious problem.

MCoupe: Get your buddy to log on and check the 993 FAQ. Its a goldmine of info. He can also search the archives for more stuff on his '96. Better yet, get him to join us!

 

Thank you all for the information! Very much appreciated.

 

Don' know about the hours on both accounts, but the carbon "fix" was done to my car by the dealer for the previous owner: $4500

The clutch I had done 2 weeks ago: $1750 or so... dealer as well...

Hope this helps.