breaking up durring boost

[danielkile]

Sooooo I have a 1998 gst swapped to a gsx with a fully built 6 bolt motor with an hx35 holset turbo with 1200cc injectors, the problem is that when I get into boost it breaks up idk if its a fuel problem or what... I put in brand new spark plugs and plug wires and messed with the spacing on the plugs and that didn't work... so then I noticed my air/fuel gauge that is normally from 14-17 was jumping to 10-11 when i got into boost so I'm kind of at a loss, and my dsm link wont connect to my computer for some as well... idk if a fresh tune would help or not, lemme know what you think. thanks a lot.

 

[majik2k5]

Start with the basics. Boost leak test. If that doesn't work, try turning your boost down and see if the problem persists. Then go from there.

 

[Animalzach]

10-11 is where you want your wideband to be reading when you get on it. When your in idle around 14 is good.

 

[WES_393]

+1 to doing a boost leak test. Boost leaks are by far the most common cause for the issue your describing. If you have an adjustable FPR, make sure your base fuel pressure with the vacuum line off is ~43psi. Like said before, your A/F ratios seem pretty normal. You want 14.7 at idle/cruising and near 11:1 at WOT if your on pump gas. However, if your running E85, your running extremely rich at WOT (probably from a boost leak). Also, if your having technical problems with DSMLink I would get them sorted out quickly. It would let you post a log as well as rule out any problems with your ECU or DSMLink.

Lastly, I would urge you to fill out your mods list asap. It's really helpful to those who want to help you.

 

[danielkile]

Alright! thanks a lot guys I'll check that stuff pronto!

oh wait!! i forgot to say my knock light comes on when its breaking up too...

 

[majik2k5]

What other supporting fuel mods are you running? I don't see any kind of AFPR or aftermarket fuel pump listed, just the 1200 injectors.

 

[danielkile]

dang i forgot to put that up, its a walbro 2551ph fuel pump...