Flat spots on cerbera!!!!

[Cerbie450]

I seem to be getting quite bad flat spots when accelarating hard from 3rd gear to 5th. Especially say at 90mph when you slap it into 3rd (which it is more than capable of doing). there is a pause for about 1 ish second and then it pulls. It does the same in 4th and 5th.

Is this correct and would a rolling road sort it out.

Ive just had the austec de-catt and ACT sports exhaust. (THE NUTS!!!!)

Help!!!!!

[GCerbera]

Could be a number of things, but normal culprits are throttle pots, ht leads breaking
down or a spark plug problem.

[dai capp]

Agree with GCerbera, but also, if you check the archives for posts on de-cats this can be a symptom of having them removed. Mine is de-catted and I have a slight flat spot at around 2,500 RPM but I find that it revs so freely without the cats that it compensates for this anyway.

Hope this helps

DC

[joospeed]

most 4.5s suffer from flat spots on rapidly opening the throttle anyway, you need a 4.2 or sp6 if you want instant response ..

[dai capp]

joospeed said:

most 4.5s suffer from flat spots on rapidly opening the throttle anyway, you need a 4.2 or sp6 if you want instant response ..

Am I right in saying that the ECU upgrade that is available through Austec can be custom mapped to get over this issue with 4.5's or am I talking out of my proverbial!

Cheers

DC

[washy]

I think the 4.5 issue is a result of where the injector is placed in relation to the throttle butterfly. I'm sure Joolz will tell us shortly.

Washy

[Cerbie450]

I spoke to Paul at Austec yesterday and he assures me that when they do the ECU upgrade is done the car will drive like a dream. Cant wait.

I suppose I will be joining the cue.

Since having the de-catts done the car is so much more responsive in all gears and easier to drive. Just need to iron out the flat spots.

cheers