... because it's overboosting like a bastard!

Been to a rolling road session at AMD Technik in Bister today, and got some suprisingly wobbly dynoplots. Martin at AMD (who has a lot of Cossie experience - and seems a thoroughly nice bloke) took it for a quick blast up the road and concluded that either the wastegate actuator or recirculating valve (did I get that right? I forget exactly what he said) was knackered!

Anyone got an idea on costs for getting it sorted?

Cheers!

 

Take it to a Tuner and get it set-up properly

 

About £60-70 for an actuator, the recirculating valve(dump valve) cannot be much from Fords.
Cannot see it being that though.



Dave.

 

Id recirc valve was fucked itd lose boost, 15quid from ford i think, for a tuner to say that id say he hanst a clue

 

What do you think it could be then, Dave? Martin was pretty sure the wastegate was sticking open, and mentioned the boost backed right off as soon as you lifted. Said the ECU was retarding the ignition to compensate - all if my memory serves me right, as here was a lot of tech. talk occuring between the AMD staff, whilst I stood there trying to keep up (I'm not currently very knowledge on these things )

 

As I say, I'm going from memory, and this guy Martin has had a couple of EsCos's and an RS500 - seemed to know a fair bit about my car.
I'm not in a position to comment really, as I know f**k all when it comes to engines, hence posting on here

 

boost would back off as soon as you lifted, all turbo cars do unless you got anti-lag

ECU retarding ign isnt so much of a problem, hitting the boost limit or detting would be

what boost was it actually running?

And if it was that bad, why the fook did they do a full run?

 

Not sure mate, but deffo has to go to someone that knows there stuff.

Like Steve said though, why do a full run.



Dave.

 

On hard acceleration the boost guage goes from one extreme to the other as you lift off. The day was a session organised for 14 of us, one run each. Another staff member did the run on my car, noticed the odd results and called Matin over. We then went for a quick drive - Martin said it'd be silly to do another run and that I should get it sorted and correctly set up. I feel I might be doing him an injustice by posting on here and not being able to recall his exact words. He really did seem to know his stuff, and judging by his firms reputation in the Audi/Porsche circles, not to mention the car park full of fine performance cars, I've no reason to doubt him.

 

he could have been discussing the amal valve...

as for the boost "backing off" its SUPPOSED to do that :P

 

If the actuator was mullered then the boost wouldnt hold, as has been said concerning a mullered dump valve.

Cant see how the wastegate can stick unless something is bent/twisted etc.

The boost is closed loop on P8 isn't it, so therefore the ECU constantly monitors and adjusts the amal valve doesnt it? It hasn;t got a bleed valve or been chipped has it?

To get 296ft/lb (assuming the reading is accurate) and the car is standard, it will have to be boosting a fair bit higher then standard.

I doubt very much that the ECU can compensate on ignition for that much boost on a standard set-up!

 

I'm aware that the boost comes of when you lift off! I was just trying to give all the facts.

So, aside for leading others to doubt the competency of the AMD boys, is there a consensus on what needs doing and how much it's gonna cost me? A new wastegate actuator at £70 plus fitting?

I'm aware I appear to be clueless on this - that's because I am!
But I'm keen to learn.

 

But if the amal valve is monked it wouldnt make that boost. Air injectors work the other way round and if they foook up you boost until you pop!

 

All very valid points... which I'm not qualified to address, except for the question over RR accuracy. My mate's standard Audi S3 (225 BHP) made 221.4 on it's second run - to be expected. A Cerbera before that made 270BHP - 90 short of TVR's figures - again, to be expected!

 

Julian,

I would get it to someone that is able to diagnose and repair the problem mate. You could end up doing some damage if you don't. Drive off boost until you get it sorted.

Good luck.

 

Thanks, that's what I was told - I'll be booking it in to a specialist sharpish.

Anyone got any recommendations in the Sussex area?

 

Did they check the fuelling on the RR run?

Unless their RR over reads, I'd say check to see if your ECU's been chipped.....

Don't forget, std EsCos DOES overboost (given the correct conditions) as it was designed to..... Worth checking plastic pipes to and from the EsCos Lektron valve (similar to an amal valve) are all connected.

 

I f it is over boosting as you say this would of shown on the rollers why did they push the engine to the limit before saying...."erm I think theres a problem" they should of aborted the run... lucky your engine didn't go pop...
As you don't say what boost it was running I suspect it was a false reading 'dabed the brakes or somthing'

 

none mate...i used to drive to peterborough to get mine looked at and work carried out.....you could try julian godfrey in heathfield who should be able to sort problem out

mark