ambient temp over 21degs causing bad running?
 

Hi peeps.

im having a problem. we have had some hot weather in the u.k. recently and im finding my 8 is not liking it. On my way way into work the ambient temp is around 10-15 degrees. The car runs fine, pulls well and ticks over ok. However, on the way home temps range from 21-28 and once warmed up it is terrible. as soon as you hit 6ooorpm there is a massive flat spot, the car surges under acceleration and the tickover sounds totally different and lower. i have no trouble starting the car from hot and i have read about the mod that can be done to redirect the water feed through the throttle body. i have new leeds and coilpacks as well as plugs. Also i have noticed the front grill is blocked off at the bottom by a rubber sheet thats fixed from behind?

Any advice greatly appreciated

If you have a scanner ..check your MAF and IAT to see if they look normal..are there any CEL's?

the only cel i get is from the lambda as i have no cat.

It is not the temps, I regularly drive my car out here in 37c temps and up to(sometimes higher) 43c. Isn't 21-28c only 70-82F? That is like winter out here and my car runs wonderfully in those temps. I can tell a little difference in performance between a cold day(60-80F) and a really hot one but its nothing major.

The throttle body mod is a great mod if you never see low temps/snow/ice but if you see those you may want to keep the coolant flowing through it.