996TT Spoiler problems...

[tezza77]

A few days ago I received a warning message on my dash about the rear spoiler (cant remember the exact message). When I stopped, the spoiler looked to be halfway up and not responding to the dash switch. I turned the engine off and back on again, the spoiler control was then working fine.

What I often see now is that the spoiler comes up on its own at the right speed but frequently fails to return (without any error messages) when I park the car. Is this a common problem? Is it easily solved or a sign of bigger problems to come?

[surfymark]

I would suggest that you have problems in store.

I had issues with mine that have been solved by now by replacing the wiring harness for the spoiler and bleeding the rams but I expect I will need to replace the rams at some point (very expensive job!)

HTH
M

[sy247]

One of my rams failed and the spoiler would not go up and down properly. I had both rams replaced and new hydraulic lines put in by an OPC. Car was collected and delivered back to me. About £1100 inc VAT.

[monthefish]

Fairly common problem and unlikely to be a cheap fix unfortunately.

[tezza77]

Bugger, thats not what I wanted to hear. There's a boat load of stuff needing doing next service.

I'll just leave the spoiler up then, problem solved for now

[Harris_I]

Had the same problem. Removing, cleaning and reoiling the rams may give you a cheap temporary solution. A few months later the rams may stick again.

Long term solution is expensive as mentioned above.

[Harris_I]

tezza77 said:

Bugger, thats not what I wanted to hear. There's a boat load of stuff needing doing next service.

I'll just leave the spoiler up then, problem solved for now

Or push it down, then remove the electrical connection. Don't remove the fuse because IIRC it's also the fuse for the engine cover latch.

[tezza77]

Harris_I said:

Or push it down, then remove the electrical connection. Don't remove the fuse because IIRC it's also the fuse for the engine cover latch.

That sounds like a good idea, thanks.

[thegoose]

tezza77 said:

Harris_I said:

Or push it down, then remove the electrical connection. Don't remove the fuse because IIRC it's also the fuse for the engine cover latch.

That sounds like a good idea, thanks.

Yes, but it might not seem such a good idea when you're spinning off the road backwards at 150mph because the car lost grip due to lack of downforce

[tezza77]

thegoose said:

Yes, but it might not seem such a good idea when you're spinning off the road backwards at 150mph because the car lost grip due to lack of downforce

Really, I have to ask how much of a difference that spoiler is making. Surely its not the difference between staying in a straight line at 150 or not. I've been in many cars at 150+ without fancy spoilers and those cars had their engines at the other end.

The car could do with being a bit more tail happy anyway

[thegoose]

tezza77 said:

Really, I have to ask how much of a difference that spoiler is making. Surely its not the difference between staying in a straight line at 150 or not. I've been in many cars at 150+ without fancy spoilers and those cars had their engines at the other end.

The car could do with being a bit more tail happy anyway

In a straight line you'll be fine, but reduced downforce when cornering will reduce the level of cornering grip available. My comment was a bit tongue in cheek but the spoiler is functional and not just there for styling purposes. How other cars achieve their stability is probably a question for their manufacturers.

[tezza77]

thegoose said:

In a straight line you'll be fine, but reduced downforce when cornering will reduce the level of cornering grip available.

Excellent

[Harris_I]

thegoose said:

In a straight line you'll be fine, but reduced downforce when cornering will reduce the level of cornering grip available. My comment was a bit tongue in cheek but the spoiler is functional and not just there for styling purposes. How other cars achieve their stability is probably a question for their manufacturers.

Knowing you are an experienced racer, Marcus, and realising your first comment was tongue in cheek, I'm sure you agree that spoiler is really not doing a lot even for the majority of track day drivers.

Trackdayers who can exploit downforce should probably be racing instead. I've done lead car duties in a 996TT (with spoiler in permanent down position) at Yas (which is a high downforce circuit), and at the cornering speeds most novices and intermediates are comfortable with on track, there's really little need for a spoiler.

[mez3]

Mine had those symptoms a year ago. Then it stopped working all together.

It was on the list of jobs to sort out when it went in for a service.

After picking the car up my other half who followed me back home from the garage said it was going up and down fine.

There was no mention of it on the bill and when I called them the following week to tell them what a massive difference the 4 wheel alignment had made to the stability of the car, especially at high speed they mentioned that the spoiler was working fine when they tested it.

How long for though who knows.

[Rockster]

tezza77 said:

Really, I have to ask how much of a difference that spoiler is making. Surely its not the difference between staying in a straight line at 150 or not. I've been in many cars at 150+ without fancy spoilers and those cars had their engines at the other end.

The car could do with being a bit more tail happy anyway

Apples and oranges. Different cars have different aerodynamics and the absence of a spoiler/wing may be compensated by something other aerodynamic features of the car.

The spoiler is like the brakes. You can get along just fine without any until you can't. I can and have driven sometimes for over an hour or more without having to touch the brakes but then I need them and now.

Same with the spoiler. You can't always know before hand when a passing vehicle's air blast coupled with a slight crest in the road will get the car floaty. If traction conditions are marginal you could be admiring the way you came through the front window instead of the rear view mirror.

Also, I note the thing goes up at an indicated 75mph (my car's odo is 2mph optimistic) but doesn't come down until the odo reaches 38mph. This delay suggests that after running the car/engine hard enough to raise the spoiler that it should remain up to possibly help channel air through the engine compartment cover to help remove heat a hard working engine has built up. While the engine is water cooled the exhaust system with those massive turbos and the drivetrain even the brakes can emit a considerable amount heat long after the engine is just idling away with its heat being removed by the coolant.

Related to the above if the spoiler increased air flow through the engine compartment it might also result in a slightly higher air pressure over the engine's air intake so if the spoiler were down the engine might not run quite as strong at higher speeds at it would otherwise.

I know the spoiler can be expensive to put right if it goes bad. But to me it is as vital as having properly functioning brakes or having proper tires on the car. If it is too expensive to fix back to its stock functionality look into removing it and fitting an quality fixed wing/spoiler setup. But I would want to be able to assure myself this fixed setup would not materially negatively affect the car's stablity at any speed and of course perform equally well those subsidiary functions the stock spoiler setup performs.

[tezza77]

Rockster said:

Same with the spoiler. You can't always know before hand when a passing vehicle's air blast coupled with a slight crest in the road will get the car floaty. If traction conditions are marginal you could be admiring the way you came through the front window instead of the rear view mirror.

I just feel its a bit of a gimmick rather than anything really useful, certainly at 75-80mph. For more extreme speeds I guess I'll see the next time I am on track but im used to handling a somewhat unpredictable TVR (what a rush, 996 turbo has nothing on that), im really not worried about the turbo. I'd really like the rear end to become more lively... the only time it wants to get jiggy is when its wet.

Rockster said:

Also, I note the thing goes up at an indicated 75mph (my car's odo is 2mph optimistic) but doesn't come down until the odo reaches 38mph. This delay suggests that after running the car/engine hard enough to raise the spoiler that it should remain up to possibly help channel air through the engine compartment cover to help remove heat a hard working engine has built up. While the engine is water cooled the exhaust system with those massive turbos and the drivetrain even the brakes can emit a considerable amount heat long after the engine is just idling away with its heat being removed by the coolant.

There could be some merit to that but I feel its more likely done this way to stop the spoiler jumping up and down like a yoyo.

I assume thats easily tested, does anyone know if the spoiler can be put down manually if doing say 100mph. Since Porsche opted not to let me fully disable the PSM, presumably because that would be dangerous , then surely they wont be having any of this spoiler down at high speed nonsense.

[Rockster]

tezza77 said:

There could be some merit to that but I feel its more likely done this way to stop the spoiler jumping up and down like a yoyo.

I assume thats easily tested, does anyone know if the spoiler can be put down manually if doing say 100mph. Since Porsche opted not to let me fully disable the PSM, presumably because that would be dangerous , then surely they wont be having any of this spoiler down at high speed nonsense.

If the spoiler were nonsense why not then have it drop at the same speed the one in my Boxster drops? It rises at the same (nearly the same speed) 75mph indicated, 70mph actual (the Boxster speedo is 5mph optimistic). It drops at under 50mph.

My limited testing is the spoiler once raised either manually or by speed can't be lowered manually until the vehicle's speed drops below the speed at which point the spoiler is automatically lowered.

[tezza77]

Rockster said:

If the spoiler were nonsense why not then have it drop at the same speed the one in my Boxster drops? It rises at the same (nearly the same speed) 75mph indicated, 70mph actual (the Boxster speedo is 5mph optimistic). It drops at under 50mph.

My limited testing is the spoiler once raised either manually or by speed can't be lowered manually until the vehicle's speed drops below the speed at which point the spoiler is automatically lowered.

I dont have first hand knowledge of the boxster but I guess the spolier does even less on it. The earlier you can get it back down the sooner you can eliminate the drag it causes which I guess directly affects economy which I'll bet is why the boxster drops at 50. I wonder if all the new Porsches drop the spoiler at 50?

You're definitely not needing that spoiler at 50 mph, I think there's something horrendously wrong with the aerodynamics of your car if that tiny spoiler is keeping the arse end down at 50-100mph. IMO the only thing its doing is reducing your drag coefficient. If the spoiler was bigger and extended higher then I could believe it was doing some good... look at the size and height of the GT3 RS spoiler, I can see that it adds a little benefit there, but my tiny little spoiler sat up a few inches... I don't buy it.

[monthefish]

tezza77 said:

For more extreme speeds I guess I'll see the next time I am on track but im used to handling a somewhat unpredictable TVR (what a rush, 996 turbo has nothing on that), im really not worried about the turbo. I'd really like the rear end to become more lively...

Be careful what you wish for. Remember where the 911s engine is compared to the TVR.

[tezza77]

monthefish said:

Remember where the 911s engine is compared to the TVR.

I do appreciate that but given my (albeit limited) experience driving the 911 in the wet its very controllable when it gets out of shape (providing you're in the right rev range so that you can get a hoof load of boost when you need it) admittedly that's at relatively low speeds compared with dry conditions.

I don't buy into scare mongering, I was once told not to buy the TVR because it would kill me one day, that it was lethal and uncontrollable... Absolute tosh, yes it was a handful but if you have a bit of clue how to drive and don't act like a tit in it then it was one of the most rewarding cars I have ever driven hard.

I think its bad to be "afraid" of any car, every driver should take their car somewhere where they can safely get it sideways and see how it bites and learn how to tame it.

That said, whilst I can handle myself in a powerful car I don't claim to be a driving god and even the best drivers in the world bin their cars from time to time so I do realise that I'm not invincible