Boost Causing Serious Backfiring

[Shagonwagon01]

My god my f*ckin sh*tty bf does the same thing!! Been trying to get to the bottom of it I originaly thought it was the fuel im running, not the case now I was told could be a blockage in the induction still not the case!

Mine idles like sh*t then all of a sudden kicks back into normal its aost like its gasping for fuel or something?

Does your engine light come on too after floggin it abit? Then dissapier after a couple days ?

[_Velocity_]

Usually coils are most noticeable under WOT but won't cause rough idle.

Sounds more like valve float. Maybe the turbo actuator's diaphragm has a split in it and is causing over boost under WOT.

[Periklis]

This just does not make sense because it was happening before I threw a rod on my previous engine, this is now a new motor with a replaced turbo, and a replaced cat...... any ideas?? this topic seems to be so popular but not defintive answer... its killing me

[Periklis]

is it a good idea to just go put it on a dyno? ive literally run out of ideas..

[_Velocity_]

Is it your original head on a new block / bottom end or did you replace the entire engine?

[Periklis]

entire motor that is why I am so confused..

[retro-xr6t]

prob worth taking to a workshop and run some diagnostics.

[boost69]

So it backfires when you give it WOT?...if the car has a generic tune to get the boost up, then you difinitely need to throw it on a dyno.

[Wenier]

When you say replaced cat, is it factory cat or aftermarket?

[spook]

Check your fuel pressue. Mine had similar symptoms to yours but funnily enough only on hot days and with less than half a tank of fuel (pump was speed was eratic). Replaced pump - all good.