rb26 surging and stumbling when not boosting

[toyota86]

delete

[RWDragoon]

Factory computer?

[toyota86]

it looks like it is the stock computer but i dont have speed or boost cut and i dont have an any aftermarket things spliced into the ecu. so im not sure

[masham]

my car has an intermittent issue. seems to be more apparent when the car is cold. when load is light and cruising and i hold the car at a constant speed at 0 vacuum or boost, it surges. only at 0, no more no less. if im in max vacuum or boosting hard its fine. transitioning from vacuum to boost is fine also. Throttle position does not seem to affect it either. it feels like a there is a dead spot at 0. also, when the surging occurs it sounds like bovs/recircs or wastegates are going on and off too when its at 0. the car is running slightly bigger than stock twins, with stock recirc valves, stock piping and an ebc. i dont think its an ebc issue either. tried a few different boost controllers. same results.

Got the same problem....:hit_head:

[judasentinel]

Seems like turbo shuffle........classic twin turbo issue when the turbos are trying to outperform each other. Since no two turbos are alike, one will almost always boost more and/or faster than the other. This causes change in pressure in the twin turbo pipe and put reverse pressure on the other turbo.

A way to counter is to get a balance pipe. Another way is to run individual pipes from each turbo to the intercooler, or as close to the intercooler inlet as possible.

There is a very detailed thread on here about this issue.

Are you using an aftermarket boost gauge? If you have shuffle, you will see your boost gauge needle fluctuate as soon as the shuffle occurs.

Try to see if your wastegates are stuck. If they are adjustable, play around with them and see if it helps.

[mcfly]

Seems like turbo shuffle

I agree, look into it and see if your symptoms are similar.
Just search turbo shuffle

[masham]

Ok, thanks for your help