MBC or Actuator?

1slowdsm · 08-09-2006

Well..I just got my car back from LSE yesterday and on the way home I noticed that my boost was out of control and my idle is crazy (but i'll figure that out soon). I've had the 14b near 25lbs and whenever it shoots pass 15 I let go of the gas. If the MBC was untouched, the boost would be the same as when I dropped off the car, right? I pre-setted it like how www.turboxs.com says, and it still doesnt control boost at all. I decreased the MBC as low as I could and still the boost is crazy. It must've been 2/3 years ago when I had a similar problem and Mike (raptor) found that it was the wg actuator. Could it be frozen from sitting for a couple months? How big of a pump would I need to use to test out the wg actuator? I just spent quite a bit of money so I want to fix this problem as soon as possible before something breaks and my money gone to waste. I have a TurboXS HP MBC. If anyone has a good MBC for cheap I'm thinking about getting a new one also.

tpunx99GSX · 08-09-2006

Make sure that the boost controller lines are going to the proper ports on the MBC. i accidently reversed them once and i was spiking all over the place and it was very erratic.

94talonawd · 08-09-2006

Check also to see if the pressure source going to the MBC is leaking.

This can be done with a boost leak test.

**JET** · 08-09-2006

Make sure the lines are zip tied too. They can pop open and lose pressure.

AlexNGreen · 08-10-2006

to test a wastegate put your hand on the vacuum port and then pull the rod out if you can't feel any suction the wastegate is bad

1slowdsm · 08-10-2006

Quote:

Originally Posted by AlexNGreen

to test a wastegate put your hand on the vacuum port and then pull the rod out if you can't feel any suction the wastegate is bad

With of without the car on? With the car off the rod doesnt move, but I dont know if thats normal or not. I just got back from the highway like 10 minutes ago so Im gonna have to wait a couple hours before I could touch anything. But all hoses are ziptied down, checked multiple times. All hoses are connected properly.

Elementality158 · 08-25-2006

It is easier to take the waste gate off to test it. like Alex said. just put a finger over the vacume line and pull it out. If it makes suction then its all good. I did the same with my car. Turns out i had the boost controller on backwards

Good luck