k to start i have a fresh rebuild with 1500 miles i just started boosting,only under full load it sputters/pops...i can give it 3/4 throttle while boosting and be fine,its just while the petals to the floor??? i have all emissions removed/greddy 720cc secondaries and a walbro..and rtek 1.7 .so i dont see how but it seem like its starving for fuel??? can a bad fuel filter do that? ps all 4 injectors are new...thanks jr...ps the timing is good

 

ps its an s4 turbo maybe pressure sensor is bad or mas airflow sensor?

 

bump for some suggestions

 

so much for tech support lol

 

do you have means of measuring AFRs or EGTs? need to know if it's rich or lean - either one can cause sputtering or popping.

what turbo are you running?
what are you using for engine management?

 

i have a rtek 1.7 greddy 720's and a walbro....running s5 turbo...on a streetport..? any suggestions

 

i have a gangrenous bunion on my third toe. do you see my point?

okay, i was a little facetious, but you have to admit you set yourself up for that.

a bad filter can cause problems. bad ignition components can cause problems. bad timing can cause problems. i doubt if you're running out of fuel with the Walbro (assuming it's the 255, right?) but your fuel pressure may need attention. what kind of regulations are you using with the pump?

more importantly, what kind of data can you supply other than a parts list?

 

Check your rpms too, to see if it is around 3K when your having the problem. Could be a problem with your secondaries. But before I worry about that I would check your fuel pressure like Diabolical said, and check my vacuum/intake piping if is all happening durring high RPMs. Anyhow good luck and keep us posted.

 

i had a simular problem, my injectors were really really dirty....

$90 fix and now my car runs like a top!...

 

i have a gangrenous bunion on my third toe. do you see my point?

souds like a boost leak to me

 

Sounds like it just needs tuned to me.

Invest in a Wideband, it's the best gauge a turbocharged car can have.

 

bump

 

got it...after all this time it was y injector air bleed plug was broken