BF xr6 turbo rough idle at a certain temp

[XRBOY85]

Hello evryone ,

 

I have a bf xr6 turbo on e85 for last 6 month

 

has 1000cc injectors and a 460 walbro pump

 

has started to have a rough idle at a certain cold engine temp the last 1 week 

 

the rough idle is more of sounding like its got a huge lift cams in it as up an down reving but it starts off slowly before it gets to sounding like that

 

its always between 50 to 65 degrees on my digital water temp gauge it does the rough idle then just within a second just straightens out idling fine till warm

 

when I turn it off when warm and let it settle for 1 hour and drop again to 50degrees and start it then it will do the same as mentioned

 

it slowly gets worse till it sounds like lumpy but clears up  straight away and picks up its idle sounding clean and stable

 

I have changed to new

 

new coil packs,

 

spark plugs,

 

fuel filter 

 

new o2 sensor dump pipeas has no cat so only one sensor

 

t-map sensor off plenum,

 

map sensor and tested also in has no vacuum leaks and even new e85 fuel

 

only thing I have not done is the engine coolant temp sensor on it 

 

 

 

anyone had a similar issue or can help as I think I have covered most thing to do

 

any help would be great/p>

[JETURBO]

Get your tuner to look at the fuel delivery request at that coolant temp which is common changeover point for a few mapped areas