dump pipe problem. please help

[99 gst spyder]

mods in profile. when i floor my boost gauges starts at vacuum 10 and slowly rising above zero while boosting. maybe gauge not accurate. another problem is that when i'm in boost starting to rise at around 4500 rpm my o2 dump pipe pops like crazy. sounds just like back firing. any help will be great. thanks.

 

[LiquidX]

Are you at full boost at the 4500 rpm?

 

[99 gst spyder]

Are you at full boost at the 4500 rpm?

no. my gauge is not accurate. it idles at 25 vacuum and when i floor it, the meter on the gauge jumps to 10 at vac and slowly boost. usually when you floor it, it jumps to zero then slowly rise on boost.

in my case, it idle at 25 vacuum and when wot it jumps to 10 and then goes up to 5 ilbs of boost right about 4500 to 5000 rpm, then my dump pipe started to backfire a lot really loud i mean really loud at wot maybe fuel cut. i can't even race, when it backfire a lot/loud, seems like the car bogs and starts pulling the car back the more i floor it. i don't know maybe fuel cut or back firing.

anyone had this problem before?

backfire usually means running really rich to me but i don't know.

i have ecm link too and only setting i change is the 2g mass, launch control at 4500 rpm, and rev limiter to 7000 rpm.

 

[BoostBuddyGSX]

i have ecm link too and only setting i change is the 2g mass, launch control at 4500 rpm, and rev limiter to 7000 rpm.

you probably have the launch control set improperly. it sounds like your two step is engaging even when the clutch is engaged.

 

[99 gst spyder]

you probably have the launch control set improperly. it sounds like your two step is engaging even when the clutch is engaged.

i'll try removing the launch control and see what happends. thanks for the info.

 

[97gst_spyder]

Also, where is the boost gauge tapped to? If its not on the P port on the throttle body, then put it there.

 

[99 gst spyder]

Also, where is the boost gauge tapped to? If its not on the P port on the throttle body, then put it there.

the boost control is tapped to the right place according to the vfaq. fuel pressure solinoid. tapped to the vacumm hose running to the center of the intake manifold to the fuel pressure solinoid.

 

[99 gst spyder]

here take a look. here some pull from ecmlink. 3rd gear all the way up till it choke on the 02 dump. when i get to 4k rpm (3rd gear), dump pipe started to back fire alot. seems like 02 was really rich but i'm not sure how to read these graphs here. knock retarted started to show more up to 7 counts.

anyone knows how to read please i need some info. thanks alot.