DME help from the experts needed
 

Hi everyone. I've been lurking on the site for months while I've been looking for my own 997. I've previously been active on the Planet-9 forums when I had my Cayman S as well as the old Porsche Pete's Boxster forums when I had my Boxster in the late 90's. I've really enjoyed this board though for the high level of technical expertise present. Anyway, on to my question.

After months of searching, I've found a truly fantastic deal on a 2005 C2S with 41,000 miles on it. It's a private party deal and has an additional 3 months of CPO warranty remaining. I had a PPI done today where everything looked good except for the DME report. Here it is. Unfortunately, they did not include the engine hours where these ignitions occurred.

• Range 1 5886
• Range 2 501
• Range 3 46
• Range 4 7
• Range 5 2
• Range 6 1

My understanding is that level 1 represents bumping the rev limiter and that levels 2 and 3 represent the same thing with forward momentum propelling the RPM alittle further. At 3 ignitions per revolution and using the lower end of the ranges on the overspeed chart we can calculate approx 16-17 seconds at Range 1 (7300RPM), 1-2 seconds at 2 (7500 RPM), and 0.1 seconds at 3 (7700 RPM).

My question is should I be worried about Ranges 4-6 given the incredibly low numbers. If my math is right we're talking about hundredths of a second here. I've also searched and some have said that DME readings can give a reading of 1 in different ranges in error.

It's a great deal and I'll kick myself to pass it up, but I just don't want the liability of a potential disaster on my hands. Plus, I cycle through cars every 6-12 months and don't want something hard to resell given that I would definitely give this information to any prospective buyers.

Thanks for any help in advance.

I think you have nothing to worry about. The range 4 and above are noise, there is no way the engine was up there for only one or two ignitions.

I'm not sure it necessarily is noise - the numbers seem consistent with there being an event where the engine did nudge, albeit for one ignition, into range 6. Ranges 4 and above are what can concern Porsche and impact a warranty, the 2005 is already out of coverage anyway. Long story short, for me at least, is that if the car otherwise checks out I'd perhaps be OK with the ranges 4 and up, but based on the range ones the car seems to have led a fairly spirited life. Someone's had some fun in that car. No bad thing, but they're no longer holding the baby...

I think it's physically impossible for the engine to be at >9500 rpm for one ignition and then get down to between 7k and 8k in 2 ignitions. I may be wrong but I can't imagine that it's possible.

You need the engine run time hours at which the overrevs happened. If long ago... with CPO warranty the car could be a find.

If not so long ago.... walk away.

If you can't get the time.... maybe dealer holding back. Regardless, walk away.

There's always another car.

Sincerely,

Macster.

I agree the dealer has the hours. If they were prior to the CPO I wouldn't worry. If it's recent it's a toss. As noted there are a lot of good cars out there. I found an '07' GT3 with zero hits in any of the ranges!

Thanks for the advice everyone. I'll be getting the engine hours tomorrow. I think I agree with everyone that if the event was remote it's less likely to be a problem in the future. I'm still interested if anyone else has an opinion.

Remember the hours info will just tell you when the last over-rev occurred. Best case for you would be if the hours showed a long time ago, maybe pre-CPO. For example if the DME shows last over-rev at 500 hours probably occurred about 20,000 miles. so if car has 40,000 miles you're probably in good shape. If the over-rev occurred at 1,000 hours I'd ask the dealer who's been joyriding. I've seen a lot worse DME readings but it will come down to how risk averse you are. Good luck

Here are the hours and the approximate mileage. The car now has 41,000 miles and was cpo'ed at 30,875 miles

* Range 1 5886 1033 hours 34,433 miles
* Range 2 501 882 29,400
* Range 3 46 788 26,267
* Range 4 7 788 26,267
* Range 5 2 788 26,267
* Range 6 1 753 24,120

It seems like the Range 4-6 events were 2 separate events, both prior to the CPO process and the most recent owner. I'm still on the fence, but have to decide today. Like I said, this is an exceptionally good deal and I wouldn't be able to find another c2s at this price.

Personally I wouldn't be afraid of this car - all of the "problem" events occurred before it was CPO'd. Good luck.

To both you and the OP: I have to agree. Well, I would not be very afraid of this car. The overrevs occured a considerable time in the past.

There is a risk -- chances are that it is a small risk -- that if something did happen that the dealer might argue because the overrevs occurred so long ago that what has happened is due to wear and not a defect and thus not covered.

Oh, and if that CPO warranty was applied before Aug. 2008 it is the original CPO warranty and a service manager told me the other day it is amazing what the original CPO warranty didn't cover.

Sincerely,

Macster.

It sounds like you have a sympathetic dealer that ran the PPI and gave you the DME information. Perhaps they can also assist you with the transfer of the CPO and somehow give you peace of mind on buying the car. Personally, I wouldn't be afraid to buy a car with that sort of DME history. I've walked on cars with LOTS of range 5-6, a car that was clearly abused. This one looks like the owner enjoyed the car and bumped against the rev limiter once in a while, but never had a money shift.