mikeTT

Sorry if this is the wrong area for this post.
Sold a 2004 911 Carrera Years ago. Had a minor oil leak covered,
no IMS issue at that time for me.
I always wanted a TT and looking at the 2007's for now.

Question is, after lurking and studying here for sometime,
how often will I find my self on the side of the road waiting for a tow?
Saw the cooling pipe issue and most say not many issues otherwise.
I do see a lot of work being done though.
Not meant to be downer.

nzskater

In 5 years of ownership of a high mileage car I've never had to call a tow truck. I've had coolant pipe issues but it was a gradual leak and I drove to the OPC to get it repaired.

Alapor

Get it scanned. Over revs can seriously hurt the lifespan of your engine. 3 design flaws that can put you on the side of the road. 1. Coolant housing jackets- Porsche used an epoxy on these and after some heat cycles it can fail. All your coolant will **** out in like 10 sec. I got mine done. 2. Plastic fittings under oil cooler- these can crack and fail. I replaced mine with steel ones from Sharkwerx. 3. Cam shafts spinning. Very rare, but can happen. 8000.00 to pin them. I am rolling the dice and not doing them.

Those are the design flaws, but in any used car a hose or belt can break, etc.... How the previous owner treated it is part of the equation. Mezger is pretty strong and hard to hurt. Biggest issue is on 6pds and over revving on down shifts. Any Porsche dealer can see if and how bad it was over revved by scanning through the OBDii port.

I think they are extremely reliable cars if taken care of and some of the initial design flaws addressed. Porsche's might be fast and exotic, but they are also tough compared to other cars in the same performance range, one thing I love about them. A lot of 997TT are daily drivers and have few if any issues.

Skwerl

Can you cite a car that had old over revs and broke because of them?

mikeTT

Thanks for all responses. It's a wonder we keep the addiction for Porsche with all the mechanical issues
but to be fair my 2013 Vet was really no different. Thanks Alapor, that is a great inventory and just have to
push to be sure of repairs before purchase. I can do some of it but the big repairs are over my head.
To all here, what a great forum!

Alapor

Why yes, yes I can. Champion Motorsports reported two blown engines from over revs. Contact Mike if you want more info. Actually, here is a quote from him- "The last 2 cars that came in here with blown motors each showed Range 5 and 6 over-revs. At that level, you're seriously testing the mechanical limitations of the engine. Eventually, it will cause a problem. Some people don't get more then one chance....it could be that one Range 5 or 6 that breaks it."

Further, Porsche has built in over revs in diagnostics. Here are the parameters on each stage of over rev-
The stock 997.1TT ranges are:
range 1 > 6800 and < 7000
range 2 > 7000 and < 7200
range 3 > 7200 and < 7400
range 4 > 7400 and < 7900
range 5 > 7900 and < 9000
range 6 > 9000

You downshift and hit a range 5 or 6, it can hurt your engine. It might not go boom immediately, but you have probably shortened it's lifespan some. Not sure what you do not understand about this. Let me simplify it. 7900 rpms or more is BAD. 9000 or more is really BAD. Metzger is tough, but not that tough. So, if you run the codes and see over revs in range 4-6,especially 5 and 6, probably best to pass.

Guy is looking for advice. Telling him to buy a 997TT with 300 range 6 over revs is probably bad advice.

Skwerl

Do you know if those range 5s and 6s were the direct and immediate cause of the blown motor? As in, guy botched the shift, and the motor went boom, and then the motor went to Champion?

Odd that with 20 years of countless examples of 996s and 997s out there running strong with old over revs, we don't see commensurately countless reports of them blowing up.

Alapor

Some cool info on all Porsche over revs. Check out the GT3. Wow.

Alapor

Look dude, if you want to buy 997TT's that have been over revved to stage 6 1000 times, rock on and help yourself. I NEVER said it would blow the engine, I said it COULD SHORTEN the life span, which if you tach a 997TT to NINE THOUSAND RPM's, it could and probably will shave some miles off the longevity of your car. Do it enough and it WILL blow the engine. The redline, probably plus a few 100 rpm's is there for a reason as that is the limit Porsche felt the engine could Tach to and still be reliable.

This guy was looking for advice on his first purchase. I gave him what I felt was good advice. Glad I did not speak to you before I bought my car. I am sure you would have told me taching it to 100000 rpm's all the time was fine, coolant pipes never fail, plastic pipes never break, cams never spin and they never break. What exactly is your point or problem? What is your advice?

Alapor

Here, read this, over rev failure. Yep, never happens.

https://www.mycarly.com/wp-content/uploads/2015/03/Carly_Porsche_Car_Check_Overrev_EN.pdf


http://support.mycarly.com/knowledge-base/like-know-background-story-carly-porsche-car-check-lost-10-thousand-euros/?utm_source=pdf&utm_medium=link&utm_campaign=overrevmanual

Skwerl

Having a bad day? (Edit: Nope, I see now that you're wound tight and needlessly lashing out is just what you do.)

I never said that overrevs can't damage an engine. Everyone knows they can and do. A bunch of recent range 5s or 6s is certainly reason to pause or pass.

However, if the guy finds his dream car that passes a thorough PPI but happens to have a handful of range 4s from 200 hours ago, that's not a reason to run for the hills. For every Carly story you find (told vaguely and with scant detail by someone trying to sell you a product...), I can find a dozen people with cars that have old range 5s running strong as new 20k+ miles later.

We see way more verifiable reports of PDKs failing randomly and requiring a $25k replacement than someone's Turbo throwing a rod from old (you're seeing that word, right? I'm not talking about a car that just had a zinger at the track 30 seconds ago) overrevs, but there isn't even 5% of the hysteria surrounding PDKs.

Finally, and most importantly, settle down.

Alapor

Not at all, I just get irritated when someone seems hell bent on challenging me and does not explain why, their reasoning or advice. Those people are generally called "trolls" because they add no value to a conversation, just trying to get a rise out of someone.

Now that you have actually stated your position, I actually agree with you on most of it. See, that wasn't that hard, was it? I disagree about old revs in the 5-6 range. If you had enough, I do not care how long ago it was, that engine will probably not see the miles a non-over revved will. Could blow tomorrow. Mezger is tough, and just because it is damaged from over revs does not mean it will blow immediately. I think a few 4's are ok. 1-3's are ok and would not discourage me. My car had 300 range 1's, about 70 range 2's, something like 25 range 3 and 5 range 4.

Let me put it like this. You have 2 exact cars. Exact mileage, year, everything and same price. One has no over revs and the other has 400 range 5 or 6. Which would you buy?

I would not buy a car with 5 or 6's, maybe a few, but not many. a handful of 4's is ok. Not worried about 1-3's unless you have 1000's of them. And yes, I think over revs should be checked before buying. Car might be beautiful and run great, but with 500 range 6, it is probably got a severely shortened life.

Skwerl

6s are tricky only because there's no upper limit (was it zinged to 15k RPM?), but if they are old and the car passes a leakdown/compression/other relevant checks and they're both otherwise in good shape, I'd genuinely be okay with a coin flip. (Honestly, the only reason I'd lean towards the former is simply to not deal with DME weenies on resale.)

I guarantee you if you've bought manual cars for long enough, you've owned a car with a "bad" theoretical DME report.

Another important thing to keep in mind is that the DME is not infallible - generally, upper range numbers under 10 or so can be chalked up as glitches.

Alapor

As the engine runs the DME constantly checks the output of each cylinder and if it finds one under or over performing will turn on the CEL and log one or more error codes. A compression test is good for the health of the pistons, rings and cylinders to an extent, but does not tell you about the whole engine such as valve train or timing. You run an engine to 9000 rpms, the cams, timing and valves are all operating in that range too.

I just think it is wise to stay away from 997TT with 5 or 6 over rev ranges and not too many 4's. I am pleased knowing mine has not spent time above 9000 rpms. 997TT do blow engines. A lot of times a cause is not apparent. Those could be from over revs.

So, I will agree it is hard to find a car that specifically grenaded from over reving. You can find them if you look hard enough. But, how many grenaded from over reving and were never diagnosed or poorly diagnosed. I just think it is safer to stay under range 5.

mikeTT

All great input! Learning a lot here.