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It was Shawn's statement, not mine, but I do understand where he's coming from.
Not a design issue, but an age issue.
The later LH (in the S4s) is known to fail eventually. Some folks have them rebuilt proactively, anticipating that failure.
Even the more reliable LH 2.2 and the L-Jet boxes are subject to failure after a long time (the "25-40 years").
These cars are at or approaching the 'estimated mean failure time'.
My 85 is now 34 years old. As such, I'm starting to wonder if & when the computer will 'just quit'. That's why sending it off and having it rebuilt (most likely by Louie Ott) is something I'm pondering as an 'over winter storage' thing.
And Erik pointed out the 'reliability' (or lack of) in newer cars. A fun one he didn't mention is an issue with the Cayenne (05 - 10). They have wires running under the driver's side carpet. Some of those wires have 'splices' that are nothing more than bare conductors crimped together, then wrapped in cloth tape. If (when) the cowl drains get plugged, water comes in through the HVAC vents. It soaks the carpet. There is open cell foam under the carpet. The carpet can be completely dry, and a couple months can pass, and the foam underneath is still saturated (to the 'drips water when squeezed' point). The 'crimped & taped' splices then corrode (conductor pretty much disintegrates) and the connection fails. The car then gives all sorts of odd dash warnings and won't crank. The fix is to dry everything out and repair the splices. Been through it.
His comment about the overall simplicity of the 928 (yes, it was one of them most advanced cars of it's time, but that was a while ago) makes me think that a properly cared for 928 could be more reliable than a newer car.
The question then becomes 'what should be replaced (and when) before it fails?'
Obviously, the TB/WP, fuel lines, maybe brakes & coolant lines.
But what about the computers? Fuel pump?
And to be clear, I don't pretend to have all of the answers to this.
I have a few opinions and am curious what other folks think.
Ya no, sorry, I know its not your quote. But..maintenance is not waiting or a thing to fail. If it's a fluid change it once a year, if it has a plug clean it twice a decade, if its a sensor replace it every 20yrs old, the heavier and bulkier the "thing" is the less it needs attention up to Trans every 100k, engine every ****-knows when.
OLD CARS mean you're painting the GG Bridge..it never ends, But every weekend or two..put a finger on 5 things, and do it.
That's a reliable car.
Or..treat it like an airplane. Take _it all apart_ once a year whether it was used or not and replace what needs done based on wear, condition, known age or service life...etc. And a plane delivered in 1960 is as good as one delivered in the 1990s or newer within the same model. It's how you approach the problem.
Failures happen, but that does not mean the same as unreliable.
Terrible! My original trans only lasted 280K miles. I rarely drove the car over 150MPH for any significant distance (only a couple of times a year in open road races and only for a hundred miles each time and never over 170 or so) and I only did burnouts once in a while after I put on a supercharger. Eventually I had to replace the trans. You'd think it should last more than 25 years of careful driving. Pitiful.
The exhaust system fell apart when I hit an 18" long oil rig pipe. Tore the rear section apart and bent the trans cable. That meant I had to drive 200 miles stuck in 3rd gear with my torn up exhaust making lots of noise. In 3rd gear I could not exceed 120MPH. NOT ACCEPTABLE! I was embarrassed.
Oh, and then there was the time my LH failed on the way to work. It was only 15 years old. It took 30 minutes for a buddy to being me a spare and get back on the road. I was embarrassed to be 30 minutes late for work, but fortunately no one noticed.
Then the radiator started leaking around one of the side tanks during an open road race. I was traveling 150-165 MPH for 100 miles. I found green stuff on the side of the car after the race. I had to wipe it off and check the fluid level. It was OK, but I didn't like seeing green stuff on the side of my car. Even though it was a slight leak, it cost me more than $100 for parts and labor to fix the darn thing. Then it did the same thing 7 or 8 years later. Had to fix it again. So, I can't say the radiator is very reliable even though it hasn't failed again and is still in the car. Someday I might have to replace it. Shouldn't it last more than 30 years?
Then you have things that are supposed to fail but won't. I tried replacing the torque tube bearing at 200K miles. There was nothing wrong with them, but since it seems a lot of people experience TT bearing failure at 100 to 150K miles, I thought it was prudent to replace them so they wouldn't fail in the middle of nowhere. Tried as hard as I could with a pipe and 5lb sledge hammer to get the old ones out and they wouldn't budge. I had to put the TT back in the car with the original TT bearings. And they are still there now with no play in the TT shaft or noise. Why would Porsche make them so hard to remove? That's stupid.
Oh, and don't get me started on the oil pan gasket and motor mounts. I had to replace them at about 150K miles. I might have to replace them again sometime. NOT ACCEPTABLE! So what if every other car on earth with that kind of miles needs motor mounts and pan gaskets too. Porsche should have made them last forever.
Wheel bearings! I actually had to replace a rear wheel bearing at 150K miles. Seriously?
So you can see why I have only driven the car 230K miles since I bought it 20 years ago. It's just too much trouble for a car that's only 30 years old. One problem after another.
The real problem seems to be the car does better if you drive it frequently. What if I just want it to be a garage queen like many other Porsche nuts? I hate that seals dry out and things start leaking and sticking and malfunctioning if I don't drive it much. So, what am I supposed to do? Drive it every day? I guess I'll have to. Darn nuisance. I should buy a trusty Honda that doesn't mind being neglected and sitting for months. I hear they are reliable with the only problem being they are very boring.
You drive a total pile of **** Bill, ya know that?
After 20 or 25 years every single wire, hose, gasket, and seal in the engine compartment is suspect. This is pretty much true for any car, except maybe a Tesla, which has about two orders of magnitude less mechanical complexity, but other issues. I always imagine pulling a car all the way down and fully renewing it with all that stuff, but never do. Which means that one of those things fails on me every 3 to 6 months. If I don't drive the car for a while, it stores up those failures and the stored failures happen within the first few months when I start driving it again. Then, after a while, we comes back to equilibrium with one failure every 3 to 6 months.
I have a long list of "maintenance" I want to do on my 1980 5-speed but the immediate needs have been met such that I drive it around wherever I want in whatever kind of traffic. I have had it less than a year and put 1000 miles on it so far. It's my fun car. My weekend car. It runs great, doesn't get hot, starts every time, sounds like a killer, and looks awesome.
Just before I got it, It mostly sat for 12 years (garaged, not a totally neglected child) with what was diagnosed as a "bad clutch" and a "no start" problem. More on that in a minute. I guess the PO was scared to have anyone less than a P-car mechanic work on it? The closest one was probably 100 miles away and towing to an unknown $$$$ bill was I guess scary, so he parked it. The car was up a mountain in nowhere Arizona. He sold it cheap to a guy that was a what I would call a capable but hobbyist mechanic. He fixed the clutch, new pivot ball (part of the clutch problem the PO didn't diagnose), new fuel filter, fuel pump, replaced cracked fuel tank, new tires, some rubber hoses, plugs, wires, etc., AND replaced a couple relays, mainly because the alarm relay was causing "no start" problems. All shipped to his house in nowhere, AZ by the wonder of online shopping. He then drove it a couple hundred miles to make sure it worked and sold to a sucker like me. I am sure I got a fair price. If the car wasn't up a mountain in the middle of nowhere he probably could have got double the price. I drove it for 4+ hours and 250 miles home without a hiccup.
I have since replaced some other parts. Rear seal and pan gasket I didn't have a lift so I hired it done at a private shop. Most other bits I changed with a screwdriver and a socket set. I'm not a master mechanic but I feel like a lot of the "bad reputation" of the 928 is a bit overplayed. Yes, it's a Porsche with some special pieces but it's a car and an old one at that. It doesn't need a computer to do most of it's regular functions like my gremlin infested POS Cadillac (sold thank goodness). Yes, parts cost more. Did you read the badge? Yes, it's gonna need new parts. Did you see the build date inside the door? Do I wish I had $30k+ lying around and could drop it with Greg for a few months? Hell yes. But in the meantime it does everything I bought it for which was to look awesome and drive barely in excess of the speed limit (for safe passing only). I have a Mazda if I really need to drive to Florida and back.
I think the key here is not to let stuff sit. Growing up as a kid (late 90s early 00s) my dad always drove old cars (mostly 70s full size GMs). To this day his newest vehicle is a 77 Delta 88 and he frequently drives his 73 Catalina, 70 Chevelle, and 75 Silverado around, sometimes up and down the east coast of the country. I know a carbureted chevy v8 isn't comparable electronically to a 928 by any means, but the point here is that despite these cars now being darn near 50 years old in a couple cases, by paying attention to things that are looking worn or starting to make noise/act funny rather than waiting for them to break, they hardly ever leave you in a situation where you are stranded. Thinking back from now to when I was a kid, I honestly am struggling to think of 5 times having a breakdown and truly can only think of 1 time that it was something that required a tow.
I've only been in the 928 game for a bit over a year now, but so far I've taken a car that had sat around for over a decade, taken care of some maintenance items, and now I've put about 1500 miles on it (not much I know) and the only issue I've had was a broken belt ac belt (right where it said made in china). I'm probably curing myself here, but I'm of the opinion that with some maintenance and just paying attention, you can catch most problems early and fix them before they leave you stuck. I mean think about it, back when these cars were new people weren't afraid to drive them anywhere, they were new cars. So why can't a well maintained old car do the same today?
CIS here. Not driven enough. Three failures in 18 years - pump ingested a foreign body in Saudi(not car's fault), radiator inlet broke off, poor fuse contact killed pump relay. Have upgraded the heavy current fuses to blade types, clean and retension all every few years. Never misses a beat in any weather, temperature, driveability cold is as good as anybody could wish. Gearbox is a bit slow to take up in reverse when cold, but apart from that is excellent. Would take it anywhere, but carry tools, pump relay and a 53. Just done all the belts. And also have road service top cover - flat bed to nearest garage from anywhere (or home if <100kms), 2 nights in a hotel etc.
jp 83 Euro S AT 57k
My experience with 928s over two decades and many, many dozens of clients is that there are few items that will kill a 928 dead and few that will strand on you the road. In general a ton of stuff can be broken and your 928 will get you home. However, if you only 'fix' a 928 when it's dead or barely running you will have a 928 that on any particular day may really worry you at worst or simply not be 'fun' to drive at best. You will have a 928 that spends an increasingly-large proportion of its time "broken" rather than available for fun use.
My definition of reliable has two parts:
A) you can get in it and drive to the other coast without really worrying about being stranded. Any car - even a new one - you jump into and drive to the other coast may leave you stranded. The key is to lower the probability to the point where you don't *really* worry about it.
B) minimize unplanned shop time by *planning* for shop time and then executing that plan so that you fix things before they break or before they become worrisome. If you do this, then your 928 has a high probability of always being in running condition and only not running at times of your choosing.
Below is a description of how I approach reliability for my 928s and for clients that wish to pursue the above definition of reliable:
1) Start with well known stranded-on-the-road failure modes that are common across the fleet or common across a specific variant. Address those items and #2 below first.
2) Baseline scheduled maintenance. This specifically includes all fluids and the timing belt system.
3) Pursue "systems" maintenance and repair rather than "point" repair. Or, in other words, when a specific component needs attention you consider the entire system of which it is a component. This is another way of writing: plan for all of the while you're in there items. For each "system" you touch you may decide to replace or not replace components based upon records, expected lifetime and/or condition.
4) Based upon a thorough inspection (for a 'new-to-you' 928) and/or historical knowledge, itemize functional issues and condition of components.
5) Based upon the above inspection and/or a full service history, develop a plan for a) servicing components that have known, expected, or 'guessed-at' lifetimes, b) keeping scheduled maintenance current, and c) addressing findings from #4 in priority order.
6) As you make use of the car, note changes in function, and add investigation of, and planning repair of, these items to your next-scheduled shop time.
If you do the above and then execute part of the plan every year during *planned* shop time you will - at some point - have a reliable 928. You can do this over a decade, all at once if wherewithal allows, or over the course of a few years in big "system" chunks.
^^ I'm surprised you didn't mention your periodic inspection guide in your signature(?) IMHO, that's the gold standard to see if a car's ready for an extended road trip. Lord knows I'll be using it this winter to make sure I'm ready for a trip to South Dakota next year.
I like that AAA will tow my car 200 miles and all, but as a community, we're pretty limited on where we could have our car towed if it breaks down. And then there's the issue of parts availability. I don't mind my car being towed somewhere and waiting a long time for a part. But I damned sure don't want it to be at a Pep Boys in Great Falls.
Many moons ago there was a list of "trusted" mechanics across the US for just such an emergency, but I think it's now legacy. Any interest in starting a new list?
Biggest part of the fun having a oldtimer is... maintenance / repair. If you want one only for driving buy a new one with warranty . And his is the same for all brands , gaskets get old an brittle on a Porsche , BMW or Mazda. They are all the same , paper or rubber. No miracles.
I have 6 oldtimers for killing time on my beloved hobby , that is 90 % working on them, 10 % driving.
No , better stated 95 % versus 5 %
^^ I'm surprised you didn't mention your periodic inspection guide in your signature(?) IMHO, that's the gold standard to see if a car's ready for an extended road trip. Lord knows I'll be using it this winter to make sure I'm ready for a trip to South Dakota next year.
A point perhaps. But, that doc's purpose was inspection and not necessarily an all-encompassing guide to pursuing reliability. Lot's and lot's of stuff would need to be added.
It also falls short since it's targeted at '87+.
That doc is also about 10 years old now. I've been accumulating notes on a version 3.
My reliability thinking exactly parallels Dave C's in post 23. I'm comfortable with throwing a bag and a set of clubs in the car and heading for the opposite coast without hesitation. To be a reasonable alternative to regional airlines it needs to be as reliable as those.
My big 928 strandings include the first, when the six year old battery wouldn't start the car in the garage after sitting a few months while I traveled. Next was stranded in the garage when the LH box gave up. I'd secured a spare and had it reworked; Rich Andrade, who did the fixin' on it, recommended that I install the rebuilt one when he did it and keep the original box as spare. I was too smart... Swapped it on failure, and sent the original for rework and have that as a spare/test box to this day. The last time I was stranded I made it all the way to the end of the driveway (~~1/4 mile steep downhill) with what turned out to be a failing fuel pump relay. Had to drag the car back up the hill, and missed a planned lunch with Greg and Rob that day. Replaced relay-relay-relay per general recommendation from Jim Bailey.
And that's it really. Over twenty years of stewardship now.
I'm fanatical about planned and predictive maintenance on all things machine. I monitor the failures that others report, inspect based on those, take appropriate action as needed. The car has had plenty of care, both proactive and reactive. My over-winter service schedule includes replacing the original fuel pumps, and it will get a new battery next spring based on this past spring's battery inspection results. It's easily reliable enough today to make that other-coast round-trip dash if asked.
I have no qualms jumping in my 87 S4 and driving it 2000kms. I worried more this year about my 10yo XC90 I use to drive to the snow, than my 928, and the XC90 is maintained reliably by a specialist shop.
The path to getting the 928 reliable was what Dave says above.. pre-empting a whole heap of failure modes (in no particular order):
1. LH failure
2. Timing chain tensioner failure
3. Timing belt system failure
4. Intake manifold engine management issues
5. Brake issues
6. Cooling system issues
7. Oil leak issues
8. Relay failures
9. Uneven tire wear/contact
10. Wiring shorts
11. Power steering fluid fires
12. Fuel system issues
When I got the car - it was poorly maintained, and out of concern for the above, I went through the car and sorted it. The list of parts fitted and replaced is significant - even bits which were still working at the time, and the cost to do so is growing rapidly with every Porsche Classic re-price. The flip side is, I get to enjoy driving it worry-free
I have a LS conversion....would be more than happy to compare reliability of the LS verse the stock 928 motor/drive train....by know means i am being disrespectful of the 928 drive train, but a huge advocate of modern technology......I am very positive my car will drive better, get better gas mileage and will be more reliable.....as far as the electrical and other aspects of the 928 not addressed with drive train, then they are equal. Obviously if you want a true 928, then you shouldn't be entertaining the comparison......I look forward to anyone who wants to test and compare drive trains.
08-30-2019, 07:32 PM
