New exhaust problems...

[Trig 0]

My original exhaust on my VR6 was knackered causing low MPG lots of juddering and massive loss of power, got a new one fitted from Longlife in Plymouth today...

 

A. Its popping on gear changes at low speed (at least only noticeable then) - never did this when my old exhaust was working ok, dont mind it but surely that'ts wasted fuel.

 

B. There seems to be less torque at low revs and I used to be able to cruise around at 25mph in 4th now it acts like its going to stall.

 

C. Lower MPG, On old exhaust used to average 29MPG now i'm on about 24MPG... this is supposed to improve with a new exhaust isn't it??

 

D. No noticeable gain in power, if anything i've lost power.

 

The car is greatly improved over the "knackered old exhaust" ride but i'm sure not as good as it was before the old one went out the window. Does this sound like an exhaust problem or is it just coincidence and actualy something completely different i.e. plugs. ???

 

Do I need to be taking a trip back to plymouth tomorrow to get this sorted?!!?

 

cheers then.

[Rob Heath 0]

The popping might be due to the fact that this new exhaust is a bit louder, so with the standard exhaust the poppin wasnt as loud, a s/s exhaust may accentuate the noise

[steveo29 0]

the standard vw system has hundreds of hours put into it to tune it to that car and engine...the longlife version is just a few universal silencers made to fit onto you car

 

i think your going to need to live with it really...alot of "perforamnce" exhausts pop on over run..the loss of torque is due to poor design compared to the vw system

[Trig 0]

Hmmm... I thought i would be getting BETTER torque and fuel efficiency with this new exhaust.

 

I can see what you mean about tuning it to the car but surely this can't be right?! Why would anyone buy a performance exhaust and replace their standard one if its a better exhaust??

[Yandards 0]

Have a read of the 'definitive what exhaust discussion thread'

 

The other problem you may have is that your old exhaust would have carbon build up etc and the engine will be tunned to your old system. By fitting a new system you have altered the back pressure in the engine.

 

The new system is much cleaner by comparison and will probably be of a slightly larger pipe bore; as such the car should benefit from an engine tune.

 

Did you have the CAT changed? Did the old CAT have anything in it? (It is not uncommon to find the internals of a CAT removed)

 

I may be talking absolute crap here.. so if someone would like to correct any errors please crack on.

[h100vw 0]

I was about to ask if the cat was removed. They stop a lot of banging and popping. My G60 Golf would flame loads on the overrun on th etrack. It would pop and bang occasionally on the road. This is often due to a weak mixture which doesn't burn as fast as a rich one. The fuel is still burnig as teh exhaust valve opens, giving the pop.

 

Are you sure you are driving it the same as before? I have been dribbling to work in my Syncro the last few days and the consumption is notably better.

 

Stainless exhausts are made of thinner gauge metal as they don't need to withstand rusting. Therefore you get a lot more noise out of the walls of the pipes and silencers.

 

I personally am leaning towards a coincidence, rather than a problem with the exhaust. Even a blowing exhaust wouldn't make much difference to the MPG.

 

Gavin

[steveo29 0]

i bet its bigger bore too.....big bore tend to offer more top end power..smaller bore help torque low down

 

ebay it and get a vag one or supersprint

[Trig 0]

Definately driving it the same.

 

Cat is still the original one & the new exhaust is a bigger bore. I'll give it a few days then ring em up and see if they have any ideas.

 

I don't really have a problem with the popping its fore the mpg thats upset me as well as the (i think) slight drop in power.

 

Thanks for the input guys!

[Critical_Mass 10]

hmm i could do with more low end torque. any ideas on what exhaust to get then gav?

[Trig 0]

**UPDATE**

 

Took the car back to longlife today, they noticed the engine was missing, new spark plug fitted and problem sorted!

Hands up to longlife - I reccomend them!

[lukeage 0]

**UPDATE**

 

Took the car back to longlife today, they noticed the engine was missing, new spark plug fitted and problem sorted!

Hands up to longlife - I reccomend them!

 

The engine was missing :shock:

[gibber 0]

I would do an ECU reset aswel so that you ECU can reset to the new exhaust.