Ok I've had my turbo setup for around a year now all was running well... Well about a month ago my car started having a problem. The cars runs really good out of boost and even in boost up to 10 psi.. I have the wastegate set to 18psi.. Engine boosts hard in 1st and 2nd but then 3rd, 4th, and 5th hit a brick wall after 10psi... It like backfires really bad and loses power...

I'm sure 1st and 2nd run good cause it doesn't boost higher than 10psi (holset hx35).. I thought maybe it was spark blow out so I got new plugs and gapped them .25 to be sure.. Runs better now but still has the issue. No CEL.. I did get a new auto zone distributor recently.. I've already exchanged it twice cause I'm thinking it might be the cheap distributor??

I'm stumped I don't wanna start pouring money into it if its something simple..

 

Is this turbo on a 350 Chevy?

 

make this topic elswere...

this is suspension and brakes topic.

no one will answer you in this topic

name also your car and what map sensor you have

 

What are your air-fuel ratios? Do you have a wide band o2 with monitor installed?
If you have a chance and can, do a data log to see what your map sensor readings are.

Best if you get this moved to the forced induction section.

 

And how does a turbocharged car "backfire"? A backfire is combustion in the intake, which usually blows back out through the air filter / inlet, and would tend to destroy a turbocharger.

Backfires haven't been common since the days of carburetor equipped engines running a lot of valve overlap and vacuum advance distributors.

An afterfire is burning in the exhaust, and what I hope the OP is trying to communicate.

And yeah, move this to the FI forum.