Down on power?

[JoshB]

Hi all,
Had my car on the Dyno yesterday and it didn’t make for good reading...


Car feels fine, pulls well enough. During the run there was a couple of puffs of black smoke from the back...?
Torque’s not a million miles away (although a tad late) but it’s well down on horsepower and at a low RPM.
Only audible note is a sucking noise on acceleration, I don’t have an induction kit fitted.

As I mentioned, the car seems to pull well enough. Part of me wants a 2nd opinion!
I’ve ordered a new divertor valve just in case. The only other thing I can think of is the CAT, the cars only done 20k in the last 8 years...

Any other ideas?

[GVK]

Needs checking out on VCDS data logging etc, and fault codes.

May have a boost leak too hence the noise?

Decent fuel as well? 98 ron?

Sometimes can black smoke oif misfiring or pulling timing due to crap fuel.

Get some liqui moly fuel cleaner through it too, great stuff.

[GVK]

I know you didn't want to mod it but a remap would give you 250hp and more fun once fixing whatevers wrong witth it to give factory 200ps.

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[JoshB]

Cheers, it is still on supermarket fuel at the minute... Once that’s run through though it’ll be VPower only from then on.
It’s just the sudden drop off after 4800rpm that bothers me though. Not that I regularly drive it anywhere near!

[GVK]

I rev mine to 7k all the time  but then I'm a bit nuts

Fuel will do it they are meant to run on 98 minimum  and if you have s diverter valve leaking that will lose power too

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[GVK]

Invest in a VCDS cable from Gendan.ci.uk invaluable for these cars to check how they are running.

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[GVK]

Me again, make sure the fuel filter has been changed, mine was changed last year and hd the original date stamped 2007 filter on it, it had mud inside.

[pudding]

Was it really 28.5 degrees in the dyno cell?  That might have something to do with it.

[GVK]

IATs in the 50s?

[pudding]

Easily. The air temps in dyno cells are waaaaay hotter than an intercooler would see out on the roads.  The ECU starts pulling timing quite aggressively past 45 deg C intake temp and adds fuel for component protection, which might explain the black smoke.  It 'guesstimates' EGT temps from some kind of funky algorithms and dumps fuel in.  It doesn't have an actual EGT sensor like the old BAM TT engines had. 

Having said all that, 112@ the wheels is terrible.  I think there is some other underlying issue there.