What the boost?

[hubbazoot]

I installed a MBC on my car and disconnected the boost control solenoid (still plugged in, but disconnected from the turbo line) from the turbo system, and I'm still getting a reading on the OE turbo gauge and am still hitting the car's built-in limit for boost when I try to turn up my MBC. If I turn the MBC all the way down, I run stock boost (about 8lb on the gauge) and I can't turn my MBC up past 10lb. I also tried completely unplugging the BCS, got the same result. What am I missing here?

The car is a '92 Eagle Talon TSi, sport clutch, boost gauge, MBC, FMIC, ARP head studs.

 

[nuclearr]

You need a boost gauge. Sounds (to me) like your hitting fuel cut.

But do a boost leak test.

 

[gst_clipse]

im going through the same problem with my 99 GST..let me kno what u find out about what it is

 

[hubbazoot]

I have a boost gauge, I'm only up to about 12lb of boost before it starts cutting out. If you remove the BCS from the system, the OE boost gauge shouldn't work.... right?

 

[relmer4]

The o.e. boost gauge is based on airflow through the mass air meter. It isn't actual boost....it's whatever the ecu "thinks". You need an actual boost gauge to see actual boost. I would suggest some engine management solutions if you are going to venture much over stock boost levels.

 

[hubbazoot]

The o.e. boost gauge is based on airflow through the mass air meter. It isn't actual boost....it's whatever the ecu "thinks". You need an actual boost gauge to see actual boost. I would suggest some engine management solutions if you are going to venture much over stock boost levels.

I have an actual boost gauge, and the ecu won't let me run over stock boost at all. I was under the impression the way around this was to disconnect the boost control solenoid. I only want to run about 15lb of boost until I get an eprom. Do I need an eprom to run more than factory boost at all?

 

[black91awdturbo]

Where do you have you MBC lines T'd at?

 

[Tigerhorns]

I just went through the same thing check my old post out on page 2 is where you would want to start looking http://www.dsmtuners.com/forums/newbie-forum/380689-bad-idle-2.html.

 

[hubbazoot]

Where do you have you MBC lines T'd at?

The MBC is in the lines right before the wastegate and BOV, I removed the T in the line that goes to the BCS. The AFTERMARKET BOOST GAUGE is in the line right before the MBC. (By before I mean on the positive pressure side of the car). I did a boost leak on the car right after I got my FMIC piping redone (about a month ago) and the system isn't leaking up to 25psi.

Tigerhorns: I'm idling fine, but I'm not quite sure what I'm supposed to be seeing on that thread that'd be helpful.

 

[FLASH1970]

I'd get a datalogger to see your Injector Duty Cycle and knock. You can't just buy an MBC and crank up the boost. You need bigger injectors, bigger fuel pump, a way to tune with, wideband...

 

[david9291]

Do you have the lines running to the boost controller hooked up properly. That is the line running from your pressure source on the inlet side of your MBC and the outlet going to your waste gate. On what I assume is an otherwise completely stock 92 tsi awd I use a turboX boost contoller with the the pressure coming from a nipple on the angled pipe straight off the turbo. I have the BCS unplugged and see 15 psi easily.

 

[dsmdeliveryboy]

You probably have a boost leak, I would also get a fuel pump or rewire your stock one.

 

[hubbazoot]

Do you have the lines running to the boost controller hooked up properly. That is the line running from your pressure source on the inlet side of your MBC and the outlet going to your waste gate. On what I assume is an otherwise completely stock 92 tsi awd I use a turboX boost contoller with the the pressure coming from a nipple on the angled pipe straight off the turbo. I have the BCS unplugged and see 15 psi easily.

I have the inlet line correctly attached. The pressure source is coming from the intake manifold for both my boost gauge and MBC. The boost gauge comes into the line before the MBC.

You probably have a boost leak, I would also get a fuel pump or rewire your stock one.

I'm going to rewire the stock fuel pump here in just a minute and see if that effects it. I'll update everyone and let you know if this works.

As for the boost leak test... the lines are good.

 

[hubbazoot]

Rewired the fuel pump, still have the same issue and now have a NEW issue.
I'm thinkin the problem is a bad MBC. I'm going to rebuild it and see if that fixes the issue.


Starting a new thread for the other issue...