Got fuel cut today.

[TSIfreek]

Well after I got the motor back in and running great now have 60 miles on it at 10 psi from a B16g. I hit fuel cut and now I know what it feels like. (It felt like the engine just shut off for a second then came back on) It was fine at 6psi test run for a couple of days. It only happens when I hit the gas hard and starts to build boost and is fine when I eaze on the gas to full throttle. I know I need a 2g mass, SAFC and injectors and a AFPR but I thought I could at least get 10 psi out of the stock 1g mass and injectors without problems??? With my 14b I was runnning 15 lbs no problem () Anything I can do to the mass? Thanks for your help.

 

[TSIfreek]

OK I took out the lower honeycombs and its worse now I tryed to turn the boost down to 8 and still gets cut??? It acually dorve and ran better with them in. I had to readjust the idle becuse it droped a 100 rpm or so.

 

[steve]

You don't need any of that stuff what you need to do is put the lower honeycombs back in, and pressure test your intake to find your boost leaks. The only reason your hitting fuel cut at 10 psi is because your metering a lot more air than is actually reaching the cylinders.

I ran my B16G with stock injectors and 12 psi for months, never hittiing fuel cut, before putting larger injectors in.

Steve

 

[joeym4130]

Like the rest said, boost leak probably
i dont know sometimes though haha... i remember when i had my 14b at 13-14psi i would hit cut until i got my EEPROM with the FC removal...
anyways,
boost leak tester first

 

[freak4jesus_bt]

I'm running a B16g, K&N, stock exhaust (except muffler), with a TurboXS boost controller. I run 14 psi all long, with no problems with fuel cut. I did experience full cut 2 times at 15 psi though. Good luck.

 

[kottyking]

I'm running a B16g, K&N, stock exhaust (except muffler), with a TurboXS boost controller. I run 14 psi all long, with no problems with fuel cut. I did experience full cut 2 times at 15 psi though. Good luck.

I have the exact same set up and i have mine at 14 psi as well and havnet had a problem with fuel cut. Definately a boost leak.

 

[TSIfreek]

Guys I think I found my problem. I had the breather line from the top of the valve cover just running into a open plastic bottle. My machineist saw this and recomened me to hook it back up to the intake pipeing. Now no more fuel cut and the engine idles and runs 10 times better. Thanks mitch.

 

[TalonJohn94]

did you plug the intake tube in the first place?

 

[steve]

If plumbing the breather line back into the intake fixed the fuel cut problem, you have to think about where metered air came from that got into the valve cover instead of the cylinders...

Steve

 

[TSIfreek]

More than likely it is my PVC stuck open like you said. I havent checked it yet but will do this weekend. Were else could it come from...

 

[steve]

Were else could it come from

Well we found the first leak at the IC ouput, leaking as soon as we applied any pressure.
The the MBC and BOV started leaking at about 10 psi, then the PVC valve, the brake booster, and the throttle shaft seals.

I'm pretty sure the IC was the main problem that caused fuel cut.

One of these days I'm going to cut a stock BOV open and see what causes them to leak so bad down the shaft from the lower chamber. I want to know if it's a bad seal or just wear.

Steve

 

[TSIfreek]

Well we found the first leak at the IC ouput, leaking as soon as we applied any pressure.
The the MBC and BOV started leaking at about 10 psi, then the PVC valve, the brake booster, and the throttle shaft seals.

I'm pretty sure the IC was the main problem that caused fuel cut.

One of these days I'm going to cut a stock BOV open and see what causes them to leak so bad down the shaft from the lower chamber. I want to know if it's a bad seal or just wear.

Steve

Hey Steve, Thanks for the help today. I found out that one tool every turbo guy needs is a boost leak tester to get the most out of the engine. We found salt under the upper intercooler piping not alowing for a tight seal. It was 1/16 thick in some areas.
We also did some WOT logs and found some high phantom knock and my boost gauge is f**ked. I think I was hitting 14- 15 psi were my gauge said 6 one problem after another. Well we will let you all know when we get everything right and hold 15 psi with NO heavy knock.