996TT, starting up after five years sitting - what to do?

[nmlss2006]

Hello everyone, I haven't been around because... the cars have been sitting. Since fall 2019.
In an effort to actually get SOME use out of them, I had the odd idea to at least get ONE moving and I was wondering what a reasonable order of operations is.
The car was parked in mid november of 2019 with the tires topped up to 50 PSI, in a garage under a cover - where it currently sits. Battery was taken out of it at that time, but no other special considerations were employed because, well, I was planning to take it back out for Easter 2020. That.. didn't quite work out.

So now the question is : what to do? I was going to move it to the lift ... somehow (that's going to be exciting...) and at the very least change engine oil and filter before even ATTEMPTING to start it.
Anything else I should consider? For reference, there are 61k mi on the car, it's one of the last produced and I've had it since early 2008. Manual gearbox. To the best of my knowledge, the car is 100% as it left the factory back in late '04 save for engine oil, oil filter and air filter - and brake fluid.
That means that yes, in all likelihood trans fluids and coolant are the factory fill and while I was TOLD spark plugs had been replaced just before turning it over to me, I never actually got written proof of that in the stack of receipts from Porsche in CA that came with it. Belts, idlers... should (?) also all be factory.
In my head, I see this as a two-stage process, i.e. first do the 'essential' work, get it back on the road for 50-100 miles, then put it back on the lift and do .. the rest (including driver side glass regulator, finally addressing the rear spoiler that stopped working on the way back from CA in 2008... etc).

Ideas, suggestions, comments welcome.

Edited October 13, 2024 by nmlss2006

[JFP in PA]

Plan on draining and replacing EVERY fluid in the car (oil, coolant, power steering fluid, brake fluid, gas, etc.) and replace the battery. Once that is done, pull the fuel pump fuse or relay and wind the engine into oil pressure. Reconnect the fuel pump and see if it will start.

[nmlss2006]

Thank you JFP, one question: I was contemplating the gas, which yes, is one of the things which are very much on my mind. The question is: Is there a reasonable way to drain it? Or, how bad is outright dropping the fuel tank to take a look inside with a borescope and see if it needs further cleaning?
The rest should be straightfoward (famous last words) and I do have a vacuum bleeder for the cooling system.
I'm somewhat worried by 'see if it will start', I have to say :).

[JFP in PA]

You can pump the gas out of the tank with an external pump, but the problem with seeing inside the tank is it is a split "saddle
" style tank, which will be a bear to get a camera to see all of the nooks and crannies.  Drain it, flush it with some fresh fuel, and you should be good to go.  Just add a large bottle of Techron to the new gas, along with a dose of Stabil. 

[nmlss2006]

Got it, thank you again. OK, let me try - next weekend, I hope I can get fluids in time - and report back.

[BoxSinit]

Hello All.  It's been a while. I am having a similar problem. My 2002 S has sat for 1-2 years. The car ran perfectly before sitting. JFP,Should I take the same course of action? It's been frustrating getting to the bottom of this. So far I replaced the battery, added new gas, checked fuse C4, replaced ignition and fuel pump relays . Tried starting fluid and it started for a brief moment and died. Not too familiar with a multimeter but working on seeing if there's power to the pump itself. Any help would be appreciated. Thanks!

Edited January 16, 2025 by BoxSinit

[JFP in PA]

What currently passes for gasoline these days deteriorates fairly quickly if not stabilized with an additive.  That un-stabilized fuel can gum up injectors and just about everything else in the fuel system if it is allowed to sit for too long.  Probably your best plan of action is to see if the fuel system is functional; to do that, you need to check both the fuel pressure and delivery rate using the test port on the fuel rail and an appropriate fuel pressure test rig.

[BoxSinit]

Thanks JFP. I guess I'm in a jam. Ive done a lot work on my car but not familiar with the testing stated above. Any tips? Do you think Chevron Techron would help?

[JFP in PA]

Techron works with working systems, systems with old fuel problems won't be helped at all.

 

If you do not have the testing equipment, you may be able to rent or borrow it from an auto parts store.  If you are uncomfortable running the tests, find someone in your area that is and can help you.  A good starting point would be to contact your local Porsche Club of America chapter and see who they recommend.

[BoxSinit]

I'm going to try to tackle this myself.

 

I see a post of yours on another forum. Where is the shrader value to connect the fuel pressure gauge? I see a diagram but not sure exactly where it is in the engine bay.

[nmlss2006]

So it ended up not being five years.

It ended up being almost seven.

The car was parked in October 2019.

I put it back on the road today - in June 2026.

How did it go? Amazingly well.

I got out as much of the old fuel as I could - and it was not all. Put in a can of Seafoam (advisedly) and 5 gallons of 'fresh' gas. Left it to think about what it had done for an hour or so.

 

Put in a new battery and turned the key - no, I had not changed the oil yet.

It caught as fast as it could prime the fuel rails. From key turn to running, less than ten seconds. I was expecting the boxer cloud - not even vaguely.

Drove it out of storage to where I could work on it, ~0.7 mi going 30 mph in fifth. It was running a little rough but not... bad.

Got it to where it needed to be. Stopped it. Went in to grab some tools. Swore because the car was not centered in the lift.

Restarted it -> it started like it did in 2008 when I bought it.

 

Centered it in the lift, up it went, changed the oil.

Oil was from 11/17 and had ~4800 miles on it - and looked, smelled and felt just fine. There's a distinctive feel to oil past its prime - this wasn't it.

Put in 5W50 - it's summer after all and this car never sees 40F weather.

Washed the thing... there are only two problems that I'll tackle in another thread.

1) AC needs charging. I have all the equiment and 30 lbs of R-134 (from Dupont... sorry, Chemours). That's next on the list

 

2) The coolant was VIOLENTLY down. As in, it took three quarts of distilled water to bring it back to level ... but there were no stains anywhere, there was no mix ... any idea where it might have gone? I shall change the coolant anyways, the car is on the factory fill from 09/2004 and the additive package is a remote memory by now, but I'd like to understand WHERE it's going.

Oh yeah, also: tires that have been sitting for six+ years and were down to 15 PSI may cause you to experience some SLIGHT VIBRATIONS for the first 10 miles of driving.

For 'did I forget I had snow chains on' values of slight.

Anyways - one more thing to love about this car. My S54 powered M3 was a LOT more difficult to resurrect after a shorter stay... but that's another story for another forum.