At Law

Can someone give me a few pointers on how to read an
engine report? I have a print out in front of me on an
05 997S and have questions regarding the interpretation
of "Number of Ignitions, range 1, 2, 3, 4, 5, 6."
Thank you.

jhbrennan

State your questions.

At Law

My questions:

Report shows
Number of Ignitions, range 1 - 5519;
Number of Ignitions, range 2 - 847;
Number of Ignitions, range 3 - 143;
Number of Ignitions, range 4 - 13;
Number of Ignitions, range 5 - 0;
Number of Ignitinos, range 6 - 0.

Operating hours counter - 640.800

Mileage: 20k.

jhbrennan

Lots of info re this topic - here's a starting point. Search will get you more. https://rennlist.com/forums/997-foru...anical+overrev

997, esq

The range 1 ignitions aren't going to harm the car, but you sure do have a lot of them. Shows the car has been driven hard, bc you get those from bumping off the rev limiter. My bigger concern would with the range 3 and range 4 ignitions.

Check out Coochas' very helpful post here:

https://rennlist.com/forums/997-foru...v-limiter.html

He provides the following description of the ranges:

Range 1: 7300-7500 RPM
Range 2: 7500-7700 RPM
Range 3: 7700-7900 RPM
Range 4: 7900-8400 RPM
Range 5: 8400-9500 RPM
Range 6: 9500-11000 RPM

Keep in mind that the number of ignitions will be many for each time the car overrevs -- bc the count is of "ignitions" (i.e., cylinder firings). So, there probably was only one incident with range 4 overrevs, which was probably a misshift (e.g. 3d instead of 5th). That said, my understanding is that range 4 overrevs can cause harm to the car and can have warranty implications.

FYI, by contrast my car at 20K has the following (the range 2/3 revs happpened in a single incident before I purchased the car CPO'd at 9.5K miles):
Number of ignitions range 1 1102 / 455h
Number of ignitions range 2 125 / 284h
Number of ignitions range 3 2 / 284h
Number of ignitions range 4 0 / 0h
Number of ignitions range 5 0 / 0h
Number of ignitions range 6 0 / 0h
Operating hours counter 581

RonCT

I've read many technical replies on this and that range 1 and 2 is not that bad. But once you get to 3 and above, damage to the engine is possible / probable. When I looked for a CPO Boxster S, I stayed away from anything with range 3 and beyond. I was amazed at how bad some of these cars were - some with loads of range 6.

Keep in mind that's the number of ignitions, not revolutions. There are 3 ignitions in a revolution, so if you have 300 count, that's 100 revolutions, which might only be 1.27 seconds at 7600 RPM (example being 300 at range 2).

Based on the car you gave the information on, I would not buy it. I looked at one car like that and the dealer was trying to get me comfortable saying "Don't worry, it's CPO" and my answer was "Will you certify in writing that if I have a warranty issue on the engine and Porsche declines it saying "abuse" because of the Range 3+ recordings, that you will honor the warranty". The dealer declined.

jhbrennan

Here's some more info -
http://www.6speedonline.com/forums/9...-over-rev.html

Words from one of the experts - Scott Slauson -
Ranges 1-3 are just 200 RPM's apart in a spread for each range just for mainly info on how you are bumping the rev limiter. Ranges 1-3 are common for just winding up to the rev limiter at 7200 , inertia will generate up to range 3 at this time. This will depend on your driving.

Range 4 is 500 rpm and encompasses two different types of engines, ones that red line at 8200 and those that shouldn't. Basically all the 987 and 997 other than the X51 or GT3 that red line at 7200. This range shows a ID on which engine or mod is in the car between the two.

Range 5 is considered the gray or warranty void area for both engines in question and is generally not good as far as Porsche is concerned.

Range 6 Is a void of warranty and encompasses the 10200 rev limit. The 10200 is the point that all the 987 and 997 engines will succumb to valve float. The 10200 has a separate minimum classification in the DME. After this range is tripped it will record ANY rev above it in the max Rev limit. This is read out in the VAL or Vehicle analysis report. Unfortunately most Dealers do not understand it either.

I should also mention that the 996 and 986 had a range 1 and 2 with the same 10200 max.


Best,
Scott Slauson
PCA Technical Expert

At Law

Thank you all for your replies.
It looks as though this history would not void the CPO warranty,
however, does it appear that these readings have damaged
the engine?
Also, how many cars have you found that do not have similar
readings?

Jim Michaels

At Law: If my math is correct, that engine has spent a total of about 45 seconds in Range 1, 7 seconds in Range 2, 1 second in Range 3, and .1 second in Range 4. My guess is that these over-revs represent failures to shift up before hitting the rev-limiter.

I know someone who got the following number of ignitions on his printout:
Range 1: 22,207
Range 2: 1,384
Range 3: 510
Range 4: 335
Range 5: 33
Range 6: 0

I think most of these represent one missed down-shift.

No, it's not mine; all of my over-revs are in Range 1.

At Law

Jim Michaels,

Has the owner of that 997 had problems?

Jim Michaels

His car is a '06 Cayman S. He worried about the missed down-shift, and his car did go into limp mode on track. Later, his engine would not go over about 6500 rpm, but seemed to run strong until reaching that point. His car has also blown white smoke while at the track, but I don't know if that's at all related. I think he's taken it to the dealer since the incident. He's been autocrossing and tracking recently, and he hasn't reported any problems to me.

I'll email him about this thread. Maybe he'll respond.

Jim Michaels

The Cayman S owner with the missed down-shift over-revs responded to my email. He now thinks there was no lasting damage to his engine. The reduced revs experienced at a subsequent track event was likely due to bad gas, so the PCA tech said. His engine seems to be running strong now.