I get a VERY brief flick on KL (usually greens occ. RED..! ) at between 3.5k & 4k when on WOT (usually 3rd, 4th & 5th) that I've been told is 'crackle' and nothing to worry about.

Can anyone explain what this is and what may be causing it..?

BTW I get no KL activity at all other than this, even at 6k plus and car runs very well.

05 WRX decat, green, PRF7B's, STI 8 TMIC an scoop/splitter + Ecutek. 1.4 bar peak boost. 276/266 at Powerstation dyno day. (Motul 300v 10/40 & 1 bottle of Millers- as mapped)

Cheers,
Jason

PS If I drive it like I stole it, hitting 6-6.5k in every gear then I get nothing.

 

..?

 

please..?

 

It usually comes between "snap" and "pop"

At that RPM and on WOT, then it is likely to be det, alhough it depends when it's happening.

The car is mapped so providing you are running on the same fuel and booster as it was mapped to, it shouldn't really being doing it, providing it was mapped right, but if say you are stuck in traffic, then nail it, you could be getting a bit of activity due to heatsoak, but you have got a big ol' intercooler on there and aren't running stupid power through it.

If it were happening higher up the revs I'd say could be a little engine noise but not at those rpm.

Could (longshot and unlikely) be transmission noise, but that would tend not to happen when you describe and would be more of a gradual build up than a spike.

Try using a double dose of octane boost and see if it quietens down.

 

Cheers mate..

Seems to coinside with hitting peak boost, which it reaches very rapidly (ie very little spool-up, more like 'snap'..!).

It did it during mapping and mapper (listening through det cans) said it's ok, so maybe it's not det..? Just I would like to know what it is and eradicate it if possible..?

 

Just had a quick run after adding 1/2 bottle OB (aprox. 50% extra based on fuel in tank) and must admit that although not gone completely, it certainly seemed better..!

Need to see how it goes to be certain, which will be a few weeks away now as we off on holiday.

Any furtur opinions welcome..

Jason