2G Top end sputter under heavy acceleration

[LilRedSpyder]

So I swapped my trans a while back and the car started missing bad. Since then I’ve replaced the following: spark plugs, fuel filter, fuel pump, maf & air filter(adapter-cone). Car has a new fuel tank and I’ve jow ran a cpl bottles of injector cleaner and use only 93 octane fuel. Checked all vacuum lines and checked that I’m not losing fire thru my wires anywhere that I can see in total darkness.
It’s only sputtering on the upper end of my gears and under hard acceleration, if I lift off the pedal and ease into it she runs strong. I also bypassed my fuel pressure regulator temporarily to rule it out as the problem and nothing changed. Anyone had this problem or have any idea what could be causing it?? Any help is appreciated.

 

[Mello]

Start with the simple. What brand plugs & what's the gap?

 

[LilRedSpyder]

Start with the simple. What brand plugs & what's the gap?

Ngk .40 I believe is what they’re factory gapped

 

[Mello]

Turbo is smaller gap. Try gapping to .028" at the most & even smaller if you still have some missing. You want as big a gap as possible without misfires. Factory spec for turbos is .028"-.031".

 

[LilRedSpyder]

Turbo is smaller gap. Try gapping to .028" at the most & even smaller if you still have some missing. You want as big a gap as possible without misfires. Factory spec for turbos is .028"-.031".

gapped to 028 and still doing the same thing. It does seem to be smoother on top end of pedal tho

 

[1990TSIAWDTALON]

If your FPR is unhooked then it isn't rising with boost at a 1:1 ratio, did you hook it back up? If not the car is running lean in boost since it only see's base fuel pressure.
Turbo cars run a rising FPR, so for every pound of boost, the fuel pressure increases the same amount in pounds of fuel pressure. 10 pounds of boost will raise the fuel pressure by 10 more pounds.

 

[Vegas Smith]

Considering we know absolutely nothing about what parts are on the car, my guess is it's fuel cut or you're running out of fuel pump.

 

[Mello]

Knowing what turbo would be nice. Filling a thorough profile would be fantastic. Running around like an ostrich with our heads up our butts is almost a waste of time.

 

[motomattx]

It sounds like it could be a tune issue if its been reworked at all, for that matter the 2g seems to have an issue in the factory tune with the knock sensor being very/overly sensitive in certain areas of the map.

 

[Evo joe]

It sounds like it could be a tune issue if its been reworked at all, for that matter the 2g seems to have an issue in the factory tune with the knock sensor being very/overly sensitive in certain areas of the map.

Have you boost leak tested it? Surprised no one has said this yet!

 

[LilRedSpyder]

If your FPR is unhooked then it isn't rising with boost at a 1:1 ratio, did you hook it back up? If not the car is running lean in boost since it only see's base fuel pressure.
Turbo cars run a rising FPR, so for every pound of boost, the fuel pressure increases the same amount in pounds of fuel pressure. 10 pounds of boost will raise the fuel pressure by 10 more pounds.

Thanks for the info. I did hook it back up, only drove like 6-7 miles and saw no change so I put it back the way it was.

 

[LilRedSpyder]

Considering we know absolutely nothing about what parts are on the car, my guess is it's fuel cut or you're running out of fuel pump.

Updated my vehicle profile, cars all stock minus the intake. I got a new oem fuel pump and new filter that are literally 2&3 days old.

 

[LilRedSpyder]

It sounds like it could be a tune issue if its been reworked at all, for that matter the 2g seems to have an issue in the factory tune with the knock sensor being very/overly sensitive in certain areas of the map.

It didn’t have this issue until after I changed the trans. 4th gear was gone in my old one, swapped with another exact trans w/96k miles. I really don’t believe the trans is causing the problem tho. And I may be new in the dsm world but definitely not auto mechanics.

 

[LilRedSpyder]

Have you boost leak tested it? Surprised no one has said this yet!

I actually haven’t! That’s something that I will be doing asap. Hopefully I’ll have time after work tomorrow.

 

[1990TSIAWDTALON]

Auto or stick car? If auto, the end clutches and seals are needing replaced. If you are a mechanic, it is easy. Done a couple. Need to put a IPT end clutch kit in mine also but 4th is still working. That will probably change when it see's the Holset HX40

 

[motomattx]

It didn’t have this issue until after I changed the trans. 4th gear was gone in my old one, swapped with another exact trans w/96k miles. I really don’t believe the trans is causing the problem tho. And I may be new in the dsm world but definitely not auto mechanics.

Where did I say it was a transmission issue???

 

[19gsx91]

Assuming car is all stock, and he did in fact only swap transmissions that would leave me to wonder a few things...

A. Please show us an underhood picture so we can get an idea if it is actually all stock.
B. Do you know how much boost you are currently running?
c. If the car is 100% stock and it was recently torn apart and was running perfectly fine before the transmission swap then my money is on a large boost leak, probably around the BOV or thottlebody.

Marty stop showing off that HX, I just picked up a billet one.. waiting for it to come in so I can send you some pictures

 

[1990TSIAWDTALON]

I'm sorry Joe, do you want me to delete it so you feel better?
I guess I can't help it...
I'll try to keep them in my build thread from now on!!!!

 

[Vegas Smith]

Mods, please delete irrelevant photos whos only purpose is to show off.

 

[LilRedSpyder]

Mods, please delete irrelevant photos whos only purpose is to show off.

Cmon now, who doesn’t enjoy a lil turbo porn...

 

[Vegas Smith]

Cmon now, who doesn’t enjoy a lil turbo porn...

Mods, ban all members who question me.

 

[1990TSIAWDTALON]

Ok.
Your banned.

That's Vegas for ya.
Love you man! We've had alot of fun!!!!

 

[1990TSIAWDTALON]

Now, BACK to this top end sputter, any other things that the OP can look over you guys? All input is always welcome!

 

[LilRedSpyder]

It’s a stick
Again, car is completely stock minus a cone filter,
No clue how much boost it’s making, I haven’t had time to buy and install a boost gauge yet.
I plan on getting the items needed to do a boost leak test asap. Between work and more work I’ve hardly got time for anything short of sleep. I appreciate all the feedback and I’ll be updating as progress is being made.

 

[E85evo]

Could be a boost leak and the car is leaning out, but you said you can creep on throttle and it’s fine?