Turbo Timer

[SimonS4MTM]

I am thinking of installing a turbo timer.

Does anyone know if they are really needed and if they actually do the job that they are supposed to?

Does anyone have one fitted, are there any issues with it?

Thanks [img]images/graemlins/audiS4black.gif[/img]

[Nige_RS4]

Been discussed before .... see this thread.

[SimonS4MTM]

Thanks, do you know where i can get a turbo timer to do this and how much it costs?

[Nige_RS4]

Here ! I think you can also get the FATT DC in black and it fits where the cup holder is on face-lifted S4's.

[img]images/graemlins/thumbs.gif[/img]

[Dippy]

The Blitz is a good unit (especially as now it has a thin display unit separated from the control box) but the instructions are all in Japanese. Also you won't be able to get a wiring harness for an Audi, so you'll have to do the wiring yourself. I would only advise this as a DIY job for people who are properly familiar with car electrics.

If you get a Blitz then consider the version which includes boost measurement, although you need to do the piping yourself (or at least that was true when I bought one).

The Defi unit is a far better unit, both in quality, features and design. It is also slightly easier to install.

If you want to do the afterrun pump mod, then be aware that this is trickier and needs parts built from scratch. However there are people on here (myself, Toasty and others) who can advise on the technical bits.

I can note that in my current job, my journey to work involves a lot of overtaking, right up to when I arrive. So when I park my car the oil temperature is usually well over 100. If I didn't have my timer, then I'd force myself to wait in the car whilst it idles and cools, such that there would have been no point overtaking all those cars in the first place!

[Carps]

OK, so if you don't have a turbo timer then how long should we be leaving our cars before switching them off. I am currently trying do do at least 5 minutes driving below 2,000RPM prior to stopping, and then a wait about a minute before finally switching off. This goes for even when my driving has been a little 'spirited' [img]images/graemlins/wink.gif[/img]
Does this sound enough, or is should I be giving it a bit longer ? My missus doesn't seem to be enjoying the amount of time it takes me to get out of the car these days [img]images/graemlins/spineyes.gif[/img]

Cheers

[toasty]

Good points made by Dippy as usual.

Remember also though that whilst the mods made by Dippy are undeniably the best way to install a turbo timer, and will offer your turbos the most protection, a simple and *free* way of obtaining the pump overrun that Dippy speaks of is just to bridge the pins of the coolant sensor used to trigger this pump. This will mean that the pump will always overun as soon as the engine is switched off (which I don't think is a bad thing) Alternativly for a bit more cost you could arrange a cabin mounted switch which would manually activate the pump (again by bridging the thermosensor)

For what it's worth, I've never managed to get my afterrun pump running the way it was intended by Audi [img]images/graemlins/24430-audibash.gif[/img](even after castle combe) So it would seem that Audi got the rating of the Coolant Temp switch wrong.

In depth details of how to modify the afterrun pump can be found here: Audi World Tech

[Dippy]

OK, so if you don't have a turbo timer then how long should we be leaving our cars before switching them off. I am currently trying do do at least 5 minutes driving below 2,000RPM prior to stopping, and then a wait about a minute before finally switching off. This goes for even when my driving has been a little 'spirited' [img]images/graemlins/wink.gif[/img]
Does this sound enough, or is should I be giving it a bit longer ? My missus doesn't seem to be enjoying the amount of time it takes me to get out of the car these days [img]images/graemlins/spineyes.gif[/img]

Cheers

Yes, that's the main reason I fitted my timer - my mates were REALLY taking the piss out of me sitting in my car for 5 mins after arriving (my wife is more understanding).

My method (which is only my opinion) was to wait until the oil temp was no more than 90 before turning off. Since I modded, and in hot weather, this would take more like 10 mins than 5.

I have taken my temp up to say 105, and then driven slowly for a good 10 mins before getting home and the temp is still 100! So that's why I suggest you base your decision on the oil temp and not on an arbitrary time period.

just to bridge the pins of the coolant sensor used to trigger this pump. This will mean that the pump will always overun as soon as the engine is switched off (which I don't think is a bad thing)

Yes, that would make it run for 10 mins all the time, even when the engine is cold. Whilst this itself can't be bad it does mean that the lifetime of the pump and electic fan will be reduced - but then again they ought to last a long time.

However what is unknown is what effect having the ECU think the sensor is reading a high temp ALL the time will have. For all you know it might decide to <beep> the engine performance???

[toasty]

Dippy,

good point about the sensor confusing the ECU, but I think this is unlikely especially considering that the red wire leading to the sensor is only positive ~11 volts during engine operation and within 10 minutes of engine shutdown.

The rest of the time it is at 0v so the ECU isn't even monitoring the sensor.

Don't get me wrong, a turbo timer is far superior, but as a cheap fix my idea does work, and could save you £1000's

I did have this happily working on my S4 for a few months until I got the Audi warranty (I removed it in a state of paranoia just incase the dealer spotted my mod and refused to warranty my car!)

I never got round to putting it back, and to be fair, if the whole engine falls out tomorrow Audi can bloody well fit me a new one foc [img]images/graemlins/thumbs.gif[/img]

[Dippy]

...the red wire leading to the sensor is only positive ~11 volts during engine operation...

That's the period I am referring to - whilst the ECU is controlling the engine.

I admire your resolve to keep your car standard. I bought my car knowing that I would mod it!

[toasty]

Fair point,

Ok then for a quid you could wire a relay with a NC contact across the sensor and the coil connected to ground and ignition live.

That way the sensor would only be bridged when the ignition was off.

A really neat solution would be if we could get some lower rated sensors that came on at say 100C rather that the current one which I've never managed to activate.

I know what you mean about modding mate, I nearly bought Joshies ABT ECU, but by the time I'd decided to get it, it was sold. Then the other week I was considering a remap, but I ended up spending the money on that damned insurance claim.

I think I will keep it the way it is now, I think I'll be changing cars quite soon anyway [img]images/graemlins/sekret.gif[/img]

[Greg_S]

it is unlikely you will need a turbo timer since on the S2 and other S Cars i believe. they already have a factory built system built in.

I know the S2 does for certain

[Dippy]

Ok then for a quid you could wire a relay with a NC contact across the sensor and the coil connected to ground and ignition live. That way the sensor would only be bridged when the ignition was off.

Make it a timing relay and what have you got?

It brings home the point that a commercial turbo timer is a rip-off for what it is. That's why I advocate the boost gauge/TT combos.

A really neat solution would be if we could get some lower rated sensors that came on at say 100C rather that the current one which I've never managed to activate.

Absolutely. I did have a quick look on the 'net for those sensors (Bosch I think) but had no luck. However since I wanted the boost gauge I'm happy with the way I did it.

[Dippy]

it is unlikely you will need a turbo timer since on the S2 and other S Cars i believe. they already have a factory built system built in.

I know the S2 does for certain

You're right, but have missed the point. The Audi system only kicks in when the WATER temperature is so high that there's a risk of vapourisation. The system is only designed to avoid air bubbles in the turbo water jackets, not to actually cool the turbos. On the S4 you really do have to drive very hard to make it activate.

As Dan points out, changing the rating of the sensor would be the ideal solution.