turbo flutter, turbulance or misfire?

[jaydenturbo]

hi all had my stage 2 remap for a few weeks now and car boosts fine and smooth lots of power in 1st and 2nd but 3rd,4th,5th and.6th gear boosts fine till 4500-4750 revs then feels like boost gs then at 5250 revs it boosts again till i hits just below limiter and i change gear of course so is it the turbo stalling or turblance as ive not yet uprated the turbo intake pipe? or could it be a slight misfire (apparantly on the codes cylinders 3/4 have a misfire even though i changed the coil packs and yet it still comes up as a misfire still made 240bhp and 268 lb of tourque and doesnt miss a beat in 1st and 2nd so dnt think its a miss fire otherwise it would mis fire all the time) any ideas and advice would be great cheers

 

[aymen_a22]

It does sound like stall however it could be the tip turbo inlet pipe collapsing as that is apparently a common problem when high power is achieved.

If you have some way to log the boost it would be good, maybe on a full throttle run in a few gears.

 

[porter555]

is it the turbo stalling

I would have thought if it was stalling you would be getting a distinct chatter noise? Traditionally i thought this was generally a sound when coming off the boost (I've had the issue myself, but because the DV was kaput) .

 

[jaydenturbo]

i always get the chatter noise when coming off the revs but even when on 2000-2500 revs when boost doesnt kick in ? dump valve is new so think thats ok as it holds boost well in 1st and 2nd jst not 3rd 4th and 5th il get a boost gauge installed next week and see exsactly whats going on

 

[aymen_a22]

You are right that you normally get a barking or chattering noise however it might not be heard as the engine speed is continually changing therefore the engine condition causing the compressor stall will only happen temporarily. You might find that when cruising at a steady speed the turbo stalls constantly which is very bad.

Sounds like it could be one of three things:
1- inlet pipe collapsing
2 - dump valve is not operating correctly
3 - an issue with the remap

Ideally you need to log some aspects of the engine such as requested and actual boost pressure. This would help to determine if the issue is with the remap or with Components.

Does it only happen on full throttle conditions or is it at any throttle position?

 

[jaydenturbo]

car feels good when just cruising along very smooth its just feels like you get a double kick of boost thats the best way to describe it it gos, has a slight pause gos again and only when on full throttle no pause if i go through the revs without putting my foot all the way down just stay smooth so in that aspect im leaning towards the tip collapsing on itself as ive got a standard one in?

 

[Captain Cupra]

Plugs mate, need re gapping to 0.7, stage 2 runs more boost and standard gap spark gets blown out by the increased boost causing a misfire, NGK BKR7E's work great with these, I had a similar symtom and it solved it

 

[aymen_a22]

I would never have thought of that but if it is that simple then wow, I wish all problems could be fixed that easily.

Out of interest captain cupra do you have an uprated tip?

 

[Captain Cupra]

I do mate yes, it's as simple as the concept of a candle and a breeze, no connection to an Elton John hit, but the more breeze you act on the candle, (higher boost) eventually it'll be blown out, hence the misfire, mine happened on full boost request circa 18-20psi and on overboost, but now with new ngk's regapped it's golden.

Also old fashion copper plugs like the bkr7e's they create a more powerful resilient spark more suited to blower motors (turbo cars)