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MPG increase and fuel cut after fitting NUR spec


JohnK

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I fitted a NUR spec cat back system a few weeks ago, still running how god intended without the baffle :D and no. 1 cat has been removed for quite some time.

 

Problem is Ive noticed the fuel consumption has gone up dramaticly (and not its not me booting it to hear the exhaust and frighten small children) and also I think I have hit the fuel cut twice now since fitting the nur spec, I have a bleed valve that is open just a tad and again has been that way for months. When i booted it the car felt like it died, red triangle on the dash, then the car takes off again when I ease up on the throtle.

 

Its a UK spec so I shouldnt be getting large amounts of boost creep?

 

I dont have a boost guage (I know, I know :twak: ) so I dont know what boost I was getting but stock fuel cut is in place.

 

Anyone have any ideas? or is this normal?

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by Bleed Valve you mean the "Bleeder-Tee" type thing ? ?

 

in the Actuator feed pipe ? ?

 

if so......

 

YES

 

YES

 

and.....YES :music:

 

Boost cut is EASILY reached if you've 1/2-de-catted AND free-flowing

exhaust !

If you've got a Bleeder-Tee thingy.... DEFINITELY Boost Cut ! !

 

and, the symptoms you described are definitely 'AS' Fuel-Cut.

 

quite a dramatic jolt ? almost worrying the first time ?

 

you DON'T want to keep hitting it until you've solved it John ! !:(

 

I'd turn the "TEE" 'off' (shut it completely) for now, just until you

get a 'Defencer' in place, I know it's a pain but better safe than sorry ?:conf:

 

FatS.

 

[ ps. only had my NUR on a few weeks but can't say the MPG seems

any different really:conf: ...what I HAVE noticed is that with the

baffle in it pulls away a bit quicker up to about 1,500/2,000 revs

????? maybe it DOES like a little back-pressure at low revs ?

I'll want to confirm this by 'playing' at York/Elvington with it

IN/OUT and see the times ]

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John

Did you have an FCD fitted at the same time?

If not, this is what will stop the fuel cut coming in.

Basically it fools the ECU into thinking the boost is at the correct levels.

Indidentally as you are not using a Boost controller and using a manual bleed valve, you really MUST get a boost gauge so you

can check what your boosting to, or go for a good quality boost controler so you can control what you want to boost to.

I had a Blitz DSBC fitted which i think is great as it measures and displays peak boost reached, it also has 4 differerent levels of boost which you can dial in at any time.

 

Sorry if you knew all this, just trying to help.

And if anyone can correct any of the above please feel free to jump in.

 

:flame Dev

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How much was yer DSBC Geeza' ? ?

 

I'm thinkin' of exactly THAT...

 

Either a Cheapo-Crapo Bleeder with an Analogue guage,

or,

a Hiper-Expensive whiz-bang Controller.

 

FatS.

 

[ps. Geez' you going to maidstone tomorrow - "Gatherings" ?]

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From memory i think it worked out around £460 fitted......

But wowee! it was worth every penny............

As well as the performance it gives you, it alows you to tailor the settings to suit.

Would highly recommend......... :flame Dev :flame Dev :flame Dev

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JohnK,

 

I agree with the sentiments of close the bleeder until you fit a fuel cut defencer.

 

Oh and of course your fuel consumption is in direct proportion to your right foot and the amount of boost. So more boost = more fuel used! No power increase is ever free!

 

Also check your PM.

 

Regards

Pete

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I will be closing the bleeder for now, what I didnt understand is that it has been set as it is for the last 6 months,with no. 1 cat gone, without EVER hitting the fuel cut, its only since i fitted the nur that its happened. I thought UK specs didnt suffer creep?

 

I will fit a FCD but at the moment Im quite happy keeping it boosting below stock cut level.

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John i dont think its creep, its just with what you already had done the NUR spec has prob just gone too far and is now removing more restriction and allowing the boost to just get that lttle bit too high?

 

I had Nur spec fitted, both cats out together with a performance induction kit and was only hitting 0.8 bar of boost om my UK.

It wasnt until the BC went in that i started hiiting over 1 bar.

 

You have done the same in reverse, your bleed valve and cat removal might have netted say just under 1.0 bar (just guessing for the purpose of the example) and then the NUR Spec pushed it over.

 

You really need some way of monitoring so you can be 100% sure of what boost yopur producing?

 

Hope this helps

 

Dave

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...........So more boost = more fuel used! ..........

 

NO REALLY ! ? !

 

Oh SH*T.... better slow down immediately.... environment....

green-house...........poor-little-kiddies.........MY WALLET ! ! !:p

 

[ same HERE Geeza... No cats... NUR... but I bet I'm only at ~0.8/0.9

at the moment = fast enough, but room for improvement ]

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JOHN ! !

 

extremely sorry for turning this into the "Geeza' & FatS Show" :p

 

Feel free to slag me down immediately ! !:moo:

 

[ Geeza', yeah found that Texaco OK and fair blast home... bit of

traffic but not bad.... Alfa 166 was going for it but moved over VERY

nicely for me..... MURK 320 Kompressor decided if all HE could do

was ~140 then NOBODY else was going past him ? !:conf:

funny the different attitudes 'innit ?:( .. worst bit = couldn't give it

any tonkin' thru Dartfod Tunnel 'cos of traffic:mad: first time thru

with the NUR on too.... ah well, needs a 10pm or later jobbie 'spose

YES, I'll try to get 'down' to the bowels and I'll try to wash it too! ]

 

[ps... if your B'Controller's down by your knee , what do you use

to turn it up/down :eek: "Mr. GeezaLength" ? ? ]

 

[pps.... sorry... VERY nice mota.. and the J'spec with you ?

could you leave me the Anteras in yer will....just in case you

understand ! ! ]

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Steve

Not thinkin of popping me clogs just yet.......!

 

The BC really only needs one turn "click" to set for the desired boost level, the levels can be dialled very easy (even in motion). Once you have set your ratios, its in the memory and you just dial that memory 1.2.3 or 4 and away you go.:flame Dev

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