what causes overboosting and is it dangerous???

 

When your boost pressure exceeds a safe limit then your engine limiter will kick in and it will feel like you've just hit a brick wall.

Normally happens on cold damp evenings where the dense air will increase your boost pressure.

Mines was chipped and running at 15psi. Im sure the limiter is set somewhere round 16-16.5psi. Ive had it a few times, all have been on cold damp evenings.

Scary Sh** when it happens.

You can also try cleaning your solenoid, which im sure causes OB aswell.

 

yes bro, it isnt good for your engine, not one little bit, theres a preset fuel cut off limit, in your ECU, if you have modded your car and added even a filter or decat, it may happen, please get it looked at.

Answers need not be to expensive, a boost guage and a dawes manual boost control device is all you need to stop it for the moment, although by doing that you may loose some of the performance gained by the mods you have got.

If you have no mods done then, you need to look at other causes, such as your actuator.

 

It really depends how much you are overboosting.

Some of the later cars (which have slightly less boost control) will exceed their boost targets once they've had a decat. It's only by a couple of psi, and the ECU reigns it and gets control back. Overboosting itself isn't dangerous in small quantities. However, if you are getting fuel cut, it's a sure sign something is wrong, and you need to get it sorted, as fuel cut WILL cause damage eventually.

If you're getting fuel cut, you definitely need to get it looked at.
If your boost gauge goes up to 1.1Bar before settling down to 0.9, I wouldn't worry unduly. Best advice is to get a knocklink, which will flash a big red light at you if you're getting detonation which is the real engine killer.