really hard to answer. my 125K miles 2013 GTS was running just fine until i had the front diff replaced by a shop. upon picking it up, they said i had had the CEL on when i dropped it off, which is not true. it now has P0344 and a variety of other codes, misfires, super hard rattly start, ringing/knocking at lower rpms, power reduced to 50% and sometimes limp mode. actuation test resulted in likely loosening of guides and supposedly they are stuck somewhere where the cam is now stuck 25 degrees in advanced.

dec 30 i sadly bumped it into a concrete column while backing out, the consensus of all porsche specialists i spoke to is that that couldnt have caused the guides or tensioner to stop working properly. it did, however, cause a slight vibration over 75mph. which was why i dropped it off at this very reputable shop to change out the transfer case.

my experience was amazing prior to that shop. even with the grinding noise of that front diff, the engine still performed amazing and it ran amazingly, never a code, never a CEL, always started the same, always ample power. i am heartbroken - and i am taking those guys to small claims court, which is something i dont look forward to. but who knows what they did during the 12 days it took them to do one day's worth of work.

had i not bumped it into that pillar, i would not have ever thought of fixing anything proactively. there as just no indication of anything. i saw a video online by a guy who is not a mechanic but just started taking engines apart. 180K mile cayenne, while the rest of the engine is totally ****ed, from A to Z, the chain and guides look just fine. which, i dont know whether that means someone changed them out at like 100K miles.

if you can afford it, or are mechanically inclined, my recommendation would be to go for it. i have been driving around with it being "broken" for at least 1000 miles. i was told not to. dont know if pistons will hit valves. every start sounds like it's about the explode. i have no other vehicle, and partially have given up on it out of frustration and resentment. and mine wasnt cheap, either, $27K with 100K miles. it went from a $100K luxury car in all aspects, visually showroom inside out, to barely accelerating.

but if my current driving it and it still running, and say downhill or totally flat at 70mph totally smooth actually, but just no power to accelerate - if this tells you anything, then it sounds like your fear of the whole thing exploding as chain related issues occur out of nowhere, might not be warranted. but then again, there are a million ways in which something could go wrong i reckon.

not sure whether any of this is helpful. i wish you better luck than i had.

cheers

 

Just scope it and see what state the chain guide is in, as mileage is not a good indicator.

 

[QUOTE=CAVU;17843957]

…Faced this with my '80 Mercedes 450SEL a long time ago. [/QUOTE


PLEASE please don’t remind me. PTSD. And don’t ask me how much the engine rebuild cost. Even though it was a good friend who ran the shop.

 

Great write up. I know you wrote about a V8. Does this apply to 2018 V6?

 

thank you @garrett376, i will have it scoped before buying anything or jumping to conclusions cuz of the mileage.

 

You bet.
Some examples for you:
Look like this and you're good (130k miles):



Just starting @103k miles:



Looking bad @117k miles:

 

@garrett376 thanks for sending those examples! i apologize for my ignorance but what exactly are we looking for in those pictures? in the first picture i dont see that silver triangle piece at all, thats to the left of the chain, why is that? is seeing that what determines if your in bad shape or not? Is that one of the guides? Thanks again.

 

The plastic is cracked/missing in the 2nd/3rd pics, showing the metal. The chain rides on the guides.

Even a good pic, doesn't show brittle material. It could fail miles later... Honestly, this is why I am hesitant in getting another.

My 958 GTS was just totaled, it had the t-case replaced by Porsche under warranty 3 years ago, the front diff was starting to make noise just when you let off throttle, a slight hum. It never got worse, but eventually, the pinion bearing would need replacement. Now, coupled with most nice ones being at 100k miles, and even just being 12 years old, I can see most will need these guides replaced for at least peace of mind.

My truck was very reliable for three years and I put 60k miles on it. I still love it, but the maintenance, or should I say, bigger common issues, on these cars is a little off putting.

 

i started researching these timing chain kits for the 4.8L v8 engines, looks like there is only one high quality option which is the OE manufacturer, IWIS and the kit is pretty pricey ($832 on FCP). I was hoping there would be an aftermarket option from one of the high quality german aftermarket brands like Elring, etc but there isnt. The only other options besides the IWIS kit is chinese stuff on amazon and ebay, and there are tons of different random chinese manufacturers making these kits at a 75% discount over the IWIS kit. Ofcourse this is not a job id ever risk doing with janky chinese parts, but there are some positive reviews on some of these kits, with pics etc, looks like some of the reviews are real. Just wondering if anyone here has installed one of these chinese ebay/amazon timing chain kits and what their experience was?

 

Just thinking a bit on how to do this cheaper: there are ways to save using OE parts by replacing only those that are actually worn out: the timing chain is usually fine - that saves almost $400. The cam sprockets are $100 each and don't wear either; the oil pump chain, which you won't change, is $80. The lower sprocket is $250 and doesn't need to be changed. The tensioner is usually fine, and that's $200 saved.

The pads themselves represent $400 in parts from the dealer. Add in the gaskets and seals you need, and you're about half price IWIS kit price, without changing stuff you don't really need to change.

 

The IWIS kit sold by FCP includes the following: Engine Timing Chain Kit Includes:

• (1) Timing Chain
• (1) Timing Chain Tensioner
• (5) Timing Chain Guides
• (1) Crankshaft Sprocket
• (2) Exhaust Cam Sprockets
• (1) Oil Pump Chain

Looks like the only thing you would need from that kit is the guides, which im sure i can find seperately. There are no gaskets and seals in that kit, are those seperate items that you have to purchase when doing this job? What are the pads your referring to?

I do see a porsche engine timing gasket set from elring for $49, im assuming those are the gaskets that you mentioned need changing.

I do also see 4 guides that you can buy seperately from porsche (left, right, upper, and center). Im assuming those 4 guides are part of the 5 guides that are included in the IWIS kit? Purchasing these separately is about $440 + the elring gasket set for $49, would be around $500 which is a significant savings over the IWIS kit. Just quickly plugging the guide part numbers into google, im already finding them cheaper than what FCP is selling them for, so should be even cheaper than that. Good to know it isnt necessarily going to be a few thousand dollars if i do need to do it. I wanted to be prepared for how much its going to cost just in case. I know the labor is the majority of this job.

As always, thanks for your help @garrett376

 

My 2012 958 is waiting for an open spot in the shop. Having all the parts, I can say that my wife is very patient.

Garrett is the man. I wanted to add a few comments.

I would recommend fasteners and valve cover gaskets, as well as the camshaft holding tool.
Fasteners are single use, torque to yield. I am not good enough to hit 6 Inch/Pounds +90. Removed ones have been stretched past their elastic stage, and have a better chance of snapping. Look at VW shops for these. Last check they were around $1 ea. Look for valve cover and timing cover. And just a bit of advice from a Boomer, maybe buy 1 or 2 extra. Drop or lose 1 and you will be a believer.

Figure out how you want to remove the harmonic balancer! You will need this for removal and install. Seems like the torque spec is pretty steep. I didn't want to remove the front, damage the radiator or buy a new balancer. I got the "holder" and it seem like it is 4' long. I'll sure I will do this in another 100k, so might as well hang on to it for then. But again, choose a proven method you are comfortable with.

Do I remember a chain tensioner in the kit? Again, this depends on your risk aversion. Probably not necessary, but ... it's an integral part. For me, it's insurance.

Tools for torquing (that's not the same as the nasty dancing I hope). Seems like you will need something with a range less than 10 in/lb. Again, doing this from memory, but many tools have 20 for their lower limit. A fairly inexpensive tool is the Fix-It-Sticks. You can use on a 1/4 ratchet and get into all kinds of places. You will have to hit the +90 degree on your own, though. You can trust the accuracy of Fixit-Sticks out of the box, unlike cheap in/lb torque wrenches.

RTV. I'm going with the spec'd material this time Locktite SI 5900 is around $24 on AMZ. You could probably pick up a tube for $7, aerosol for $17. For me, this was worth the extra $20 knowing this would not be the failure. Book shows about 40 hrs (?) labor for skilled labor. I would hate to rework or settle for a leak.

I'm old. I like to pinch pennies. But I've also seen too many times where I wish I would have taken that extra step. I'm not trying to scare you, just speaking from my experience. Snap a head on the last timing cover fastener, and that $30 for new ones will seem like a bargain. A leak at the valve cover has driven me nuts because the RTV I chose was not the correct viscosity and did not fill the gap effectively. +$20, count me in. And I feel like a really old man saying this, because I remember thinking the man who told me this was old when he said it to me. Be careful stepping over dollars to pick up pennies. This is a big, doable project. There is a reason shops charge $ thousands. An extra $100 tactically spent may be an investment in time and money.

Good luck,
Mike

 

Can anyone tell me the torque spec and procedure for tightening the cam sprocket bolts on a 2013 4.8?

 

going to slightly resurrect this thread. I saw this while googling if timing chains are a common issue on the V8s (doesn't seem so), but wanted to get peoples thoughts, is this reddit post below an indicator that you've got broken guides?

https://www.reddit.com/r/MechanicAdv...chain_concern/

 

Looking at the picture, not seeing the issue.