[DCampbell]

Without video its hard to explain exactly whats going on but basically when the turbo sounds like its at full boost it blows off immediately and the car jerks (think of a person who isnt smooth on the clutch kinda lurch) and then it spools back and blows off and that will keep going until you let off and let it completely vent pressure.

Cant accelerate past 5k rpm because of this and I dont want to do it many more times and have it cause engine issues.

Anyone have any ideas or similar problems

Running 100 oct fuel and just replaced the sparkplugs so I dont think its a detonation issue however this is the first turbo'd car I have owned and am pretty much a noob when it comes to dealing with the whole forced induction thing.

(On the plus side I dont have the dreaded low RPM stall issue so there is that...-poke-)

If anyone can kinda point me in the right direction I would appreciate it since I know its not really a TADTS issue

 

[kell211]

It's been awhile since I've messed with turbos, but it sounds like a bov problem. See if you can adjust the spring pressure, the boost your making may be overwhelming it and causing it to open. Some you can adjust, some you have to buy stiffer spring for. Look at the top of the bov, there is typically a set screw and a nut.

 

[DCampbell]

I will look into this for sure :bow:

 

[kell211]

For that matter, the wrong port on the bov could be being used. Make sure if it has 2 ports, use the one on top, not on the side.

 

[Deja Vu]

What's your engine management solution? Another possibility is that you are hitting fuel cut.

 

[lotus90]

What psi are running? Do you have boost gauge?

 

[bri3d]

Start by getting the gear you need to know what's going on. If you're going off sound to judge boost, you're going to have more problems in the future.

You really need a way to measure what your engine is doing when you're running FI, doubly so with a turbo. A boost gauge for everyday use and data logging (timing + knock especially) for when you have issues.

Without concrete information it's really hard to tell what's going on. It could be that your BOV is too loose or damaged, could be that your wastegate isn't actuating correctly and you're getting boost surges, could be improper or leaky vacuum/boost routing to the BOV, could be detonation leading to ECU fuel cut or pulled timing, could be... all "could bes" until you have real info.

 

[BCspeed34]

Get a boost gauge and a wideband AFR if you haven't already. These are ESSENTIAL for any turbo setup.

As others have said it does sound like a BOV issue. Make sure the lines are routed correctly and that it is suitable for the amount of boost you are running. While you're at it check the lines going to the wastegate as well.

 

[DCampbell]

It was the BOV spring. I toned the boost down to 10psi (was 15) and changed the spring and its running like it should. Thank you guys.