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YOUR RESEARCHGiven two cars with equal care, which is more reliable and durable: 993 or 996?
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cel (check engine light) due
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Reported cause
The most costly 993 problem is the CEL (check engine light) due to seconday air injection passages that tend to clog up.
Given two cars with equal care, which is more reliable and durable: 993 or 996?
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Leading evidence: 'cel (check engine light) due' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'cel (check engine light) due' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Replace some tranny parts too' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Suggestion
Also if oil gets in the tranny from the seal, it means replacing some tranny parts too.
Given two cars with equal care, which is more reliable and durable: 993 or 996?
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Hello:
I'm in the rather nice position of being able to choose between two equally well-cared for vehicles: One is a '96 C4S, and the other a 2000 C4. What are the reliability issues that might make one a more durable piece than the other? They both have approximately 60,000 km [approx 36,000 miles,] both have full service records that indicate full care and attention.
Thanks for any insight you may have,
Dave in Canada
This is a loaded question to ask since it has been 'discussed' at length in the past.
My advice (coming from a 993 owner) is to drive both as much as you can, several examples of both that is. Your heart will tell you which one you prefer.
As far as problematic models, they all have their issues, but neither are 'lemons' for the lack of a better word.
For a 996, get one with a warranty as RMS problems can rear their ugly heads. The most costly 993 problem is the CEL (check engine light) due to seconday air injection passages that tend to clog up. This requires engine disassembly to clean them out. This is typically a $5k job from a dealer, maybe less from an independant?
Sounds as though Porsche doesn't work on the 996 engine's, they just replace them. This could get costly if your out of warranty.
Drive both, then decide...
One thing that applies to either model, you HAVE to post pictures once you get one
I would agree with Chris on driving both. They are fairly different cars. The 993 is more traditional while the 996 is more modern. Which you prefer is a matter of taste (I couldn't decide) and should drive your purchase rather than maintenance.
Contrary to what Chris said, the 996 engine can be worked on just like any other Porsche engine. The difference is that in 99 Porsche started an engine swap program that allows you to trade in your old engine for a new or rebuilt one from Porsche for somewhere around $7k. This is actually a great idea when comparing it to the cost of having an air cooled engine rebuilt at the local Porsche shop. The new/rebuilt engines come from Porsche ready to install so there is very little labor involved.
As for the RMS problem, there is a fair chance that you will have to deal with it. I'm not sure of the cost but I don't think it is anymore than fixing the 993 CEL (carbon buildup) problem. Either way, if you are going to own a Porsche, don't spend your last dime buying it. You will need to maintain it.
Jim
RMS is an $800 job if the crankshaft bore is concentric (most likely), otherwise it means a new engine. Also if oil gets in the tranny from the seal, it means replacing some tranny parts too.
However, RMS leaks tend to appear towards the initial lifespan of the car so at 60,000Km, it is likely to have happened already if at all and been has fixed. Sometimes it may happen twice in the same car, but its more unlikely. The car that I have heard of with the biggest milage getting an RMS seal leak is mine at 50,000Km. A �500 job in my case. The CEL problem on the 993's on the other hand will probably be the opposite and happen more likely towards the end of the lifespan.
As a side note, I would never base my desition on 993 vs 996 based on minor reliabilty/durability issues. Like has been said before, drive them and see what suits you best. Thats what really will matter in the end and you may regret it otherwise.
Hello again, and thanks for your welcome feedback:
A small question, gentlemen, and one that betrays my ignorance of flat-six watercoolers: What's RMS?
Thanks again,
Dave Jorgensen
Rear main seal. Very basically, I believe it is like a gasket that is located where the engine and transmission are bolted together. Obviously, I am a salesman, not a mechanic.
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