Fuel Problem under load with video...Please help

[2gHiBoost]

First off, I appreciate any help or advice given.

I ran into this problem about a month ago. I was coming home from work and got into boost and it hit around 12 psi and I let off. The next day, I noticed it idled ok but it would stutter anywhere from slowly rolling to wot. It would be fine if I was just cruising but as soon as I did wot, it would build to about 5 psi and stutter consistently.

I posted on dsmtalk and got several responses such as boost leaks, fpr, fuel pump o-ring, etc.

I did a boost leak test and found a leak under my greddy type-s and fixed that which helped with the stuttering at low rpms. But the stuttering continuted under full throttle.

I just put in a Walboro 190 yesterday and have driven it about 50 miles since. It still does the stuttering right aroun 9psi. It prevents it from building any more boost and I usually let off quickly after it does it, not wanting to hurt anything.

I also changed the fuel filter about a week ago. I hate to keep investing money in stuff that isn't fixing the problem. I know those are maintenence parts that need to be replaced anyway so I can't be too mad.

I went out today and took a video of the boost and air/fuel gauges to show the stuttering. I didn't stay in it long so you have to pay attention. My mods are listed below...

14b Turbo
Apexi Intake
Greddy Type-S
2.75" Turboback exhaust
Walboro 190lph
Homemade MBC

Here's the video..

http://s84.photobucket.com/albums/k35/cardguy13/?action=view&current=MOV00689.flv

Nick

 

[diablos991]

Maybe its the homemade MBC.

Have you checked your turbo for shaftplay?

 

[2gHiBoost]

See the thing is, I've had the MBC on there for the last 2 months and this problem just started last month. I guess I could take it out just to troubleshoot it.

As for the turbo, when I did the boost leak test, I checked for shaft play and there was little to none. Turbo is in good condition.

It just sounds like its running out of fuel pressure in the upper rpms. I am just trying to get some help on this situation without buying a new fpr if thats not the problem...

 

[2gHiBoost]

I forgot to add that I have also replaced the plugs with NGK Platinums within the last 2 weeks. Hopefully someone has had this problem before and can help me out.

Thanks!

 

[The_EE]

Dont use plat's. Use NGKBPRE7ES.

 

[2gHiBoost]

Ok, I will have to check those out.

I heard on another thread about a guy who was having bad sputtering during idle and mid throttle but under acceleration it was fine. Kinda sounds like the opposite of mine but his was the o2 sensor giving out... Any thoughts on my problem being in the same boat as this? Just confused still....Thanks for the inputs!

Nick

 

[Rahdigga8188]

In the video your bov sounds pretty distinct. Are you venting? I know when I did that for a little while to let my wife hear the nice woosh it ran like crap. Just my .02

P.S. Guys in the other pics in the album.... wow, makes me miss my old partying days

 

[Bmxr152]

Do not use platinums, they will melt off in the cylinder and casue lots of problems for you down the road!

 

[andymoraitis]

Ok, I will have to check those out.

I heard on another thread about a guy who was having bad sputtering during idle and mid throttle but under acceleration it was fine. Kinda sounds like the opposite of mine but his was the o2 sensor giving out... Any thoughts on my problem being in the same boat as this? Just confused still....Thanks for the inputs!

Nick

I say it's your crappy platinum plugs. Mine had them when I first bought it and it did the same thing. If you can find NGK 6's or 7's, Autolite 63's will work fine. With respect to the O2, if your A/F gauge is cycling normally then it's fine. If it's sluggish then I'd replace it.

 

[2gHiBoost]

Thanks for the replies. I will go down and pick up some NGK's tomorrow or the next day and try them out. Will definitely let you know how it goes.

As for venting, I am recirculating to my injen intake. Its loud cause the windows are down.

As for the partying, yeah, this semester has already started off with a bang . I don't have the toughest schedule this semester so I'm taking advantage of it...