I have a MY99 UK. When starting in the mornings (wet or dry) and gently pootling up the road until it warms up, at a steady 2 to 2.5k, you can feel the power or boost fluctuating slightly in a pulsed way. Its very suttle and you can only just notice it (especially as its up hill).

Does NOT do this at the end of a 9 hour day on the way home,
just after its been left out all night.

Is that normal ? Has anyone else noticed ?

Cheers,

MKC

[Edited by MKC - 8/16/2002 6:08:57 PM]

 

It did this both before and after I had a new engine, injectors, ecu, heads & turbo..!

 

Yup.
That's right.

 

Amazing...a similar thing ocurs as the boost spools up and is held sub boost when its warm, not very smooth when increasing revs slowly either...is that all normal (again very suttle)??

Never had this on my Escort RST, Calibra Turbo, Supra Turbo, Rover 620 or 220 Turbos (modded or standard). Not too impressed with that...

Ta...C

 

My own personal pet theory (no one else seems to be too convinced by it ) is that there are 'interesting' things going on inside the air inlet at the point at which the pressure inside the air inlet is similar to outside (i.e. during spool-up), which muddles the fueling, etc. Anyway, changing the length of this inlet (cold air intake, etc.) seems to get rid of the 'problem'.

 

I find when the car is stone cold you have to press your foot far further on the gas before the car will try to boost up and even then it'll do so reluctantly. This doesn't concern me in any way as most cars struggle a little when cold and because of this it's very easy to drive off-boost until she is nicely warmed up.

 

Gents, remember that Scoobys have a different set of fueling algorithms for cold start. You should expect different behaviour when starting from cold anyway.
Also Saxo Boy I wouldn't be tempted to encourage the car to boost up when the car is 'stone cold', not unless you want to cause longer term reliability problems.

 

Seems most do it, mine (uk99) used to do it 'slightly' but its really noticable since I fitted a new MAF a little while ago

I have read that the 'cold start' fuelling is to blame for this and once the air temps rise the 'normal' fuel map comes into play, then things level out.

Anyway, I can live with it...cos I luv it when its going well