Question for the Apex guru's

[DirtBoss]

I have a 2006 Apex with a GT25 Boondockers on it. Ran great all day until the way back down to the snowpark. As soon as it starts building boost it falls flat on its face. After stopping and letting it idle for a minute it would run fine for a pull and then back to the same issue.
Seems like a fuel issue to me, maybe the pump is going bad? This kit uses the stock pump in the tank.
Had anybody had this issue and thanks in advance for any help.

 

[ryan7]

Boost problem

Check the connection where the sender attaches to the BD box in the nose of the sled. this is where the BD box senses presure from.

 

[DirtBoss]

Checked the boost line to the Pure Logic controller and it is fine.
Maybe the controller went bad???

 

[maniac mechanic]

Take a small pump and pressure up the hose to the controll box, when it is idleing. The blue light should lite up and the sled should flood. if neither happens, then you know the box is hooched. seen a few of them boxes quit sensing boost.

 

[DirtBoss]

Thanks Quantum! I will try that out.

 

[DirtBoss]

No luck yet!

Box is working. Tested fuel pressure at the rail is a constent 43 lbs. Hits 7 lbs of boost and falls on its face. Fuel pressure stays at 43 lbs.
Anybody have a clue where to look next?

 

[EZmoney]

Check for a boost leak if you havent done so yet.

 

[maniac mechanic]

the fuel pressure should got up with the boost. anywhere from 1 to 2 extra pounds of fuel pressure to every pound of boost. if it is not going up, then your regulator is not getting a boost signal. so you have a loose hose or a kinked hose. like EZmoney said, check for boost leaks. your box might not be seeing boost either.

 

[Pastor]

You most likely have a big boost leak.

You may have a fitting that is still on or looks right but has lost it's ability to hold boost.

Check you brackets that hold the inner cooler down, if one of them is broken, you are probably losing boost from the bottom of the throttle bodies where they attatch to the head, I have seen this happen twice. Both times we could get about 7lbs before it would fall flat on it's face.

Check between the inner cooler and the throttle bodies.

Check below the throtle bodies where they connect to the motor.

Check just after the turbo, the hoses that connect to the inner cooler.

Check to make sure your Blow Off valve does not have ice in it. Take it off warm it up, clean it up, dry it out and put it back on.

From what you are describing you have a boost leak OR your control box has come unplugged, or your box is not getting a boost reading because of a tube that has a leak in it or kink or come unplugged, therefore no fuel is being added when boost begins.


Do you have a Boondocker Box? If you do, you can clear your boost numbers and see how many pounds you are building. If all XXX comes up it has come unplugged. If you are building 6-10 lbs you probably have a big boost leak.

 

[Pastor]

Did you figure it out?

 

[DirtBoss]

Thank you Pastor

You hit it on the head.
One of the innercooler bracket was broke and under a normal inspection you could not see the break. Under boost it would lift up and create a leak between it and the throttle bodies!
Headin for the hills and thank you guys for your wisdom.

Todd

 

[Pastor]

That is great!!

We had two of them break and the pressure was lifting the throttle bodies off the motor.

So you would look at all the normal spots that you might lose boost and you could not see anything.

You had to get a flash light and look where the throttle bodies attach to the motor itself.

Really glad for you that you found the problem and will be able to ride again soon!

Merry Christmas!