Ok i have noticed that after work when the engine on my 91 rs is stone cold (12 hour night shift, so its air temp) i have noticed that if i rev it out of gear it will runn up about half way and then lag, then with a bit more throttle go on up. The odd thing is though that when i put it in gear and run it down the road at wot or 3/4 throttle there is no lag. Is this something i should worry about or just run on the theory that if it aint broke don't fix it?

 

i wouldnt worry bout it