Thread: Idle = AFR problems

i have localized the knock sound and it comes strongest between 3rd and 4th cylinders. i don´t belive that the tensioner makes so much knock noise there...

hydraulic lifters i don´t have! It the GTI-R engine!

I have the exact same noise on my Highport SR20DE, have changed tensioner and fitted Roller Rocker lifters, but the noise remains....

I also have an Innovate wideband hooked up, which shows around 18 on idle...

now i have changed the tensioner and some shims from the valve train. The knocking sound i hear is much lower.

BUT what is it if the engine knocks (read the power fc approx 50 level) when the engine is cold? If the engine is warm all is ok. Any idea???

at idle you can have a more leaner air fuel ratio as you arent under any loads with that.

if you have a means of adjusting your air fuel ratios you can just add some fuel in where the car idles, but either way it wont have any ill effects. i have had my air fuel at idle lean and rich just depends on your setup and how your cams respond to more or less fuel

yeah the car runs spot on the plugs are the perfect colour, I do have an ASP budget header which Im pretty sure is leaking where the pipes merge from 4-2 and 2-1 on the inside where they have not been welded... I know if this is the case it would be causing the wideband to read lean... has anyone else with a budget header experienced this? it is a very noisey header....

as soon as you start driving the AFR's come down to perfect levels, I think this is due to the design of the header as once the gases are flowing they cannot leak as much if you get what I mean...