Thoughts on a high mileage but Porsche cert 991.1?
#1
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I was not really looking for it, but a casual scan and I found a nice 911 C4S with PDK and lots of options that’s Porsche certified with full two year warranty. But it’s got 80k miles on it. I was out on my Ducati and stopped by to take a look. It’s super clean. You’d never know it had that many miles. All service records too. So it’s all up to date with belt, oil and filter, pdk service, spark plugs and more. Had my bike gear on so didn’t drive it. But will tomorrow. Sooo anyone in here got a high mileage 991.1? Thoughts?
#2
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It’s my experience that cars that actually get driven end up being far more reliable. These cars will happily live very long lives. I personally wouldn’t hesitate for the right price.
#4
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I was not really looking for it, but a casual scan and I found a nice 911 C4S with PDK and lots of options that’s Porsche certified with full two year warranty. But it’s got 80k miles on it. I was out on my Ducati and stopped by to take a look. It’s super clean. You’d never know it had that many miles. All service records too. So it’s all up to date with belt, oil and filter, pdk service, spark plugs and more. Had my bike gear on so didn’t drive it. But will tomorrow. Sooo anyone in here got a high mileage 991.1? Thoughts?
#5
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go for it, do the usual PPI stuff and enjoy! if the car was maintained properly, should be no issue
#6
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I have a 105k mile 981 Cayman S and it has been very reliable, even standing up to repeated track days. So I would have no concerns with an 80k mile CPO car in terms of reliability, plus you have the warranty to back it up.
Only issue I had was a maintenance issue related to the intake valves and carbon deposits as a result of the direct fuel injection. It caused a mid-range rpm hesitation (especially at part throttle) and loss of power. I had to walnut blast the valves, which was a pain on the Cayman due to the mid-engine layout, but I think to do it in a 911 it would be even harder without dropping the motor down.
People will say this isn't an issue on these engines but I guarantee those people have never looked inside a high mileage Porsche DFI engine. It happens to all DFI engines eventually due to the lack of gasoline (with detergents) washing the valves. May or may not be an issue at 80k but I would bet by 100k it starts to run rougher until it's cleaned out.
Only issue I had was a maintenance issue related to the intake valves and carbon deposits as a result of the direct fuel injection. It caused a mid-range rpm hesitation (especially at part throttle) and loss of power. I had to walnut blast the valves, which was a pain on the Cayman due to the mid-engine layout, but I think to do it in a 911 it would be even harder without dropping the motor down.
People will say this isn't an issue on these engines but I guarantee those people have never looked inside a high mileage Porsche DFI engine. It happens to all DFI engines eventually due to the lack of gasoline (with detergents) washing the valves. May or may not be an issue at 80k but I would bet by 100k it starts to run rougher until it's cleaned out.
#7
Three Wheelin'
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People will say this isn't an issue on these engines but I guarantee those people have never looked inside a high mileage Porsche DFI engine. It happens to all DFI engines eventually due to the lack of gasoline (with detergents) washing the valves. May or may not be an issue at 80k but I would bet by 100k it starts to run rougher until it's cleaned out.
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#8
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Well not all DFI engines. Some use port injectors on the manifold in addition to the high pressure direct injectors, and this configuration is specifically used to address the carbon build up on intake valves. My Tacoma had 12 injectors for its V6, and plenty of those running around with 200k+ miles and never needing walnut blasted valves.
#9
Three Wheelin'
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I wonder if it’s a packaging issue, or some other performance related reason. These seem like otherwise fantastic engines, crazy strong internals and a stock fuel system that has LOTS of headroom for more power. I guess compared to older air cooled turbo 911 motors, that seem to be out every 30k or so miles having their top ends rebuilt with all new valve train, having to walnut blast the valves every 100k may seem not that a big of a deal to Porsche.
#11
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It’s a nice car. At some point the sports front bumper was added. The 80K service was done, by the dealer. New tires all around. Brake pads and rotors done short time ago. No coolant or oil leaks after it warmed up. If it was manual I’d probably buy it, but it’s pdk so still thinking about it. Not much info about how pdk is at that mileage. Granted you get two years of warranty so it would be covered in those two years if it took a poop.
#12
Burning Brakes
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If you like it, then go for it. I have over 108000 on a 2012.5 C2 with PDK. Techs routinely comment that it's trouble free because it's driven.
#13
Rennlist Member
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2015 Targa 4S - Sitting in Phoenix, 6,800 miles down the road on a summer road trip. 2,200 to get home. Odometer went through 86K yesterday.
It a leak, squeak or rattle. Health permitting, I will do it again next year.
Not a secret, timely maintenance will keep these cars running forever:-)
If u like the car, go for it!
It a leak, squeak or rattle. Health permitting, I will do it again next year.
Not a secret, timely maintenance will keep these cars running forever:-)
If u like the car, go for it!
#14
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It’s got a Insta 360 camera on the windshield with the connectors being routed to it under the headliner. No big deal. But it’s also got some weird looking OBD2 connector in it, via a cable that goes to the actual port on the lower dash. I have no idea what this is, perhaps some odd tuner thing. I’m quite surprised that Porsche certified this car with the weird connector just sort of laying there. These cars are too sensitive to hacked electronics being present, cause if I bought the car and problems happened, they might blame it on said parts and deny a claim. The dash cam is no big deal, but that other cable is sketchy.
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JeepJLU2020 (06-30-2024)