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Discussion Starter · #1 ·
i'm noticing the car "surging" a bit when accelerating in fifth gear.....put my foot down, the car goes, then i can hear the turbo whistling for a couple of seconds, then it drops off, then whistles again, but my foot is in a constant position on the accelorator.

so whats the score with this guys??

is it a collapsing hose??.....if so, which one?...part numbers, pics, prices, as much info as possible!!

its also a bit lumpy in lower gears......give it a blip of about two seconds in second, lift off the accelortor and it feels a bit "lumpy".......normal?...or do i need to learnt to "drive" my car again?
 

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Could be timing pull.
What you may be feeling is a slight drop in power due to heat created from higher boost coupled with warm ambient temps.
What settings and fuel are you running?
 

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Discussion Starter · #3 ·
running standard revo settings, on the 98 ron setting.......

running bp ultimate.......

it aint so much a drop in power, but the turbo stops whislting......

if it were to be a collapsing hose, which would it be?
 

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Had the same when running Revo trial, never did get too the bottom of it as it cleared up once the trial finished.

Currenty on the Jabba GB so will wait till they have it to see if any problems occur during remapping.

One thing i have noticed is i gave the MAf a good clean the other day, as i was having power issues when changing gear at high RPM's, the clean has seemed to clear this as i've been giving the car some stick today and feels alot better [:)]
 

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Does it do the same on a lower setting?
Is it 95ron on SPS2?

Im pretty sure 98ron settings would be timing 6 which from what I have seen on rolling road printouts its too much in some situations when ambient temps are a little high.
Try a lower setting or stick some octane booster in and see how you go.
 

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Yes as thats your only way of lowering your timing settings.
Its worth a shot.

I was running timing 6 with Optimax and octane booster so had 99ron which was spot on when logging.
You are currently running Ultimate which is 97ron - not 98ron.
 

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Discussion Starter · #8 ·
i was thinking of going back to place of installation to get them to check the settings.

will runing the 95ron setting have any ill effects??

such as MPG, or bad running?

apologies for the dumb questions, but i'm rapidly feeling out of my depth!
 

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If you are retarding on your 98ron map then a 95ron map may actually feel quicker due to no timing pull.
There will be no ill effects at all.

Why run 97ron fuel on a 98ron setting though?
Ultimate = 97ron, Optimax = 98ron.
Also remember that high boost, high ambient temps and a poor SMIC are also a killer when it comes to timing pull.
Always better to run slightly less timing under those situations.

So either drop to 95ron settings or start using Optimax with octane booster and try again.

Disconnect your battery for a minute to reset ECU settings after switching to 95ron map.
 

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Discussion Starter · #10 ·
If you are retarding on your 98ron map then a 95ron map may actually feel quicker due to no timing pull.
There will be no ill effects at all.

Why run 97ron fuel on a 98ron setting though?
Ultimate = 97ron, Optimax = 98ron.
Also remember that high boost, high ambient temps and a poor SMIC are also a killer when it comes to timing pull.
Always better to run slightly less timing under those situations.

So either drop to 95ron settings or start using Optimax with octane booster and try again.

Disconnect your battery for a minute to reset ECU settings after switching to 95ron map.
ok.......stupid question............not understanding the timing?

also, do i NEED to disconnect the battery?...aint that the point of the SPS2 to just be able to change?
 

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Yes, let the ECU re-adapt to your new Revo settings.

It has to be timing related really as you will struggle with 97ron fuel on 98ron settings in the colder months, never mind when its a little warmer.

This is where an SPS3 comes in as you could drop timing down by one notch instead of two.

Revo map (95) - Timing 4
Revo map (98) - Timing 6

I think you would have been better on timing 5, maybe contact your Revo dealer and see if they have a SPS3 to change your timing settings?
 

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oic!

you mean as in let the revo re learn?

timing is beyond me but i'll take your word for it!
Gary is talking sense, either octane boosted or retard the timing. The only way you can retart the timing with your SPS2 is to drop to the 95 setting. If you did not reset your ecu (battery disconnect) it will take a fair while to adapt.
 

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Take it back to the dealer - they will be able to drop the timing down a notch i.e. to 5 using either an SPS3 or using the Revo program and cable.

If that doesn't resolve the issue they should also be able to do a datalog run, this can then be reviewed and passed onto Revo if required.

The ambient temps are up at the moment due to our fine weather and if you are only running 97 it could well be pulling timing like Gary said.

BTW we don't charge if our customer have to come back for a datalog run - even though in most cases it is a problem with a stock componant, and usually the MAF [:(] although we did have an Ibiza where the coilpacks was the problem once.

You can also reset the adaption using VAG-COM without having to remove the battery, so get them to do it while they are in there.

Hope you resolve it.

Paul
 

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Discussion Starter · #20 ·
if i knew what retarding the timings meant then i might........ [:$]
So you are not going to try the 95ron map?
This will retard timing by 2 notches on an SPS3.
yes, i will try the 95 ron map........

do i HAVE to disconnect the battery to do it????

what does retarding the timings mean?remember i'm just a newibe to all this tuning mularkey!!!
 
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