Since fitting a new exhaust system (full inc manifolds) my engine seems a bit chuggy :( I remember reading somewhere on another forum (yes I said it) that there is some ritual you can do so that the ECU accepts the new part and makes the necessary alterations.Some thing to do with giving it a good ragging,turning of the engine, turning the key in a certain way and restarting etc. can anybody remember how to do this and and tell me how or post a link up to the instructions either on here or on another forum (yes I said it again,lol)

Try that "old chestnut" where you reset the ECU by disconnecting the battery :unsure:

How long does it have to be disconnected for so it does that ?? And how does the ECU do it ??

I'd leave it off for an hour or so... It will be shite to drive until it re-adapts !!

i had that when the guys reloaded my auto box softwhere took a couple of day to settle down now its fine

Cheers guys :)

Do I have to take it for a run straight after reconnecting ??

STILL RUNNING LUMPY AFTER 300 MILES :( :( :(

Disconnected the air mass meter and to see if it made a difference.....not a bean,so maybe thats now knackered ??

Its fine after 2500rpm but lumpy as porridge up to then ??

Any ideas ???

Whats the mpg like? BTW you did the right thing takin her for a run !

Personally I would start with the air-flow and work towards the engine methodically, I mean filter/box, hose, MAF, hose, Throttle-Body and tightness/seal of their connections. Then if you're happy that everythings ok then move onto fuel and timing.

I cannot really help 'coz I'd need to get in there to solve it :(

well I havent got an air box,got an induction cone.The bit just before it with wires commin out is that the air flow meter/MAF ?? If so thats the bit we disconnected to see if it made a difference (in a bad way) to how it was running,it didnt :)

But why would it go like that afer JUST having the exhaust changed ?? Them bits werent touched so surely cant just suddenly stop working ??

This could be because the "back-pressure" from the standard exhaust has disappeared almost completely, causing confusion with Engine Management !

It's like, carburettors would need re-jetting with a similar pipe setup eh?

So whats the fix dude ??

Re-map?

Did you disco the battery BEFORE the pipes were fitted?

MUCH DOLLAR :(

on the cards but def not so soon :(

Looks like I could be stuck with it a while then :(

No didnt disco the battery before/while pipes fitted.Did it dy after when realised how lumpy it was

Brief explanation of standard pipes...

Fitted at manufacture to comply with emissions first and foremost.

Help the engine by holding/slowing the flow of burnt gases to stop the engine from revving above recommended levels (this is why F1 cars can rev twice as high with the help of crank/con mods) this preserves the engine's life. Because of this, ECU will advance/retard the ignition to compensate and deliver the best firing time to the cylinder.

Thanks for that..........I think,lol..............Im still no wiser,lmfao :D

Hehehehe, the point I am trying to make is that your new pipes might have given your car the lumpiness :rolleyes:

QUESTION.............could it be cos Im using 95 octane juice ?? ie cos of the change in exhaust pressure,air intake,slight power change,ECU reset etc etc could it be cos I should now be using 97+ octane ?? Just an idea cos my ex gf's Scooby used to run perfect on 97+ but totally !Removed! on 95 ! And before you say it yes I know that my Beemer is no Scooby,or has the power like a Scooby.Its just an idea ??

TBH Dave, I can't see that being the issue mate ;)

Me either,was just an idea and worth a try ;)

Have you considered a diffo throttle-body?

Like the M52 one or even the 3ltr/3.5?

Just a thought buddy... Dunno the part numbers yet but OEM site would give an idea :huh: :unsure:

Would you say its chugging coz its not gettin enough fuel?

Even changing the plugs for higher/lower temp ones might cure it...

The only time its chugging and lumpy is between 2000-3000rpm if thats any help ??

Decided to bite the bullet and booked it in to my garage for next week !! TBC.................

good luck mate.hope it aint too expensive