I finally got my password sorted and had a play with the liquid gauge (It's still not fitted so no pics yet). Not good unfortunately!

I have had the engine management light on for a while now after a problem with my coils (which was fixed) so I knew there may have been a problem but it drives fine. I know that sometimes the codes just need resetting and the VAG specialist I go to said it all appeared fine but he'd go over it with a fine toothed comb today while he's fitting the rear bushes.

Anyway, I plugged the Liquid gauge in and stopped a few times on the way to the garage to record bhp, torque and 0-60 times all of which were measured in the manner recommended by the manufaturers of the Liquid (just not on totally flat roads).

The results were:

145bhp

181lb ft of torque

8.4 seconds 0-60

My mods are in my sig so you can see why I'd be unhappy. It certainly doesn't feel that slow and I'm not looking into the 0-60 time to much as it was tested at minus 3 degrees C. Wheelspintastic is the word I think.

The fault codes it threw up were 17763, 17769 which relate to the coils which I expected and 17608 which isn't listed in my list of codes. Anybody help with that one?

Will those fault codes mean that the engine management on the car is limiting it's own performance? I haven't noticed a massive difference but with the weather and the lack of fast straight roads I've not been able to test the performance properly for at least 3 months. Overtaking still seems easier than when it was standard though.

Cheers guys

:confused: :confused: :confused: :confused: :confused: :confused: :confused: :confused:

Is that not your wheel BHP? or does the liquid guage take that to be at the fly?

Ah. I don't know actually. I'll check the manual. What would 145bhp at the wheel translate to at the fly? I know it's not an exact science but roughly?

No way will a car as heavy as an Octy do 0-60 in 8.4s on 145bhp flywheel. I think you must have a power output at the drive there.

Like I said don't read too much into the 0-60. It was minus 3 and a bit slippy to say the least so I struggled to get what power there was down on the road.

By the same token that you don't read too much into your 0-60 you shouldn't read too much into your hp figure, it's only a rough mathmatical calculation and not a substitute for a properly operated and accurate rolling road.

Have you input the correct weight etc into the guage?

I know that it's not exact but it has been found to be within 1hp of a rolling road by people who know what they're on about (not me) so it is supposed to be pretty damn accurate. There doesn't appear to be anywhere to input data such as weight.

And while I shouldn't read too much into the hp figures it's a bit of a big difference. I was expecting well in excess of 200 especially given that it was minus 3 celsius.

The power figure is probably a derived power too. I don't know how the LG works, but I wouldn't place any credence in one figure taken from a run where I got a dubious value for another figure.

I agree that it should be accurate in theory however I was trying to, in a round about way, say the same as Ken does, if you discount one of your figures then you must discount the others as they are probably linked. It is a calculation, much like the Butt Dyno I would guess.

AudiWorld Forums: "Butt Dyno" Instructions

You need to enter the weight of the car as this is critical to the calcution.

mine is spot on had no probs and is within 2bhp off 3 different rr's

firstly you have faults so get them cleared and remember the liquid gauge can only show you 4 fault codes so you may well have a few more...

get a code reader out on the car sort them out and then re try. if there still a problem give them a call at race diagnostics really helpful and they will sort any probs out..

by the way not heard of 1 having a problem yet though.....

Westallc - Did you enter the weight somewhere?

if you discount one of your figures then you must discount the others as they are probably linked.

The only reason I was discounting the 0-60 was because I was wheelspinning trying to get off the mark. It did take about 8.4 seconds to get there but it took so long because I couldn't get the power down on the slippy road.

Measuring the bhp you put the car in 3rd, drop down to below 1500rpm then floor it until it reaches the rev limiter and there was no wheel spin there. Bit of a nightmare test, as the rev limiter in 3rd is around 100mph I have to go to my mates house with his private road which isn't exactly flat but should give a good enough reading.

Westallc - Did you enter the weight somewhere?

No mate plug and play.....

put the guage on bhp and floor it in first this should give you your peak in that gear wich should be 200 + possible:thumbup:

Nice one, will try that when I get it back. Why doesn't it give max in 3rd then?

If you're wheel-spinning off the line this gives one of 2 likely scenarios:-

1) Too much wheelspin, which will mean that you take longer to reach a given speed.

2) Ideal wheelspin, which gives the optimal 0-60 time. As earlier, no way would a standard 150 manage a sub-9s 0-60 time anyway.

A power figure derived from acceleration data, without the configuration data of car mass and actual gear ratio, is going to be an "at wheels" guesstimate, and a flywheel figure taken from a rolling road is a guess too frankly.

Are you sure about the standard 150 figures Ken? The figures on Parkers.co.uk for the standard 1.8T Elegance at 150bhp is 8.1 seconds 0-60 with the standard VRS hitting the same in 7.6 seconds.

Nice one, will try that when I get it back. Why doesn't it give max in 3rd then?

it should if you have it on dyno as the manual says but try this way and see what you get. will identify if there is a prob:thumbup:

let me no the outcome:thumbup:

I've managed to find that fault code 17608 relates to Boost Pressure so that could be something to do with it. I've called the garage and they're looking into it.

do you have a standard dv???

3. 17608 P1200 = Problem with DV or N249/N75 valve to fix = clean and regrease DV and/or replace N249/N75 valves

17608 - boost pressure control valve (N249) : mechanical malfunction:thumbup:

Yeah it's standard. I've heard mixed reports about the standard dvs but I thought I'd stick it out until it breaks. Which is possible now. I'm awaiting the verdict...

Yella, what BHP were you expecting?

One thing that can cause an incorrect BHP reading is a faulty maf, if it is on its way out it will read low.

Faulty mafs seldome throw up fault codes too.

Have a look at your maf readings and compare to a know good max reading.

Cheers

The power figure is probably a derived power too. I don't know how the LG works, but I wouldn't place any credence in one figure taken from a run where I got a dubious value for another figure.

The liquid calculates BHP from the engine air consumption, 0-60 times are unrelated to this.

However to record a good 0-60 time you really need to be shown how to do it properly and practice a lot, you have to be extremely brutal.

My best time is 5.6s but took me in excess of 30 launches to get it, = fecked clutch

The liquid calculates BHP from the engine air consumption,

That's very interesting. My engine consumes more air at 4_000 rpm on a closed throttle than at 2_000 on full throttle, but burns no fuel on a fully closed throttle at anything over 1_200, so makes no power.

Edited 14 January, 200917 yr by KenONeill
Typos!

That's very interesting. My engine consumes more air at 4_000 rpm on a closed throttle than an 2_000 on full throttle, but burns on fuel on a fully closed throttle at anything over 1_200, so makes no power.

I am working on a diesel version at the moment so if you can can show a maf log for the conditions you highlight I would be very interested.

FYI that the maf data is reported in a completely different way on the vag petrol and diesel engines. On petrol it is shown in grams per second and on diesels it is shown as grams per stoke, so the revs reed to be taken into account.