shutting down

typhooey

New member
I know this has been talked about but I cant seem to find it,when I boost launch as soon as it gets ready to shift to 2nd the truck drops on its face and the engine light comes on.any ideas before we start guessing 1 question that little silenoid on top of the turbo,does it matter how the vacuum lines are hooked up,1 from the wastegate and the other from itself.
 

dgoodhue

BuSTeD 4.3
Re: shutting down

SeattleSy#1255 said:
yes it matters how the vacuum lines are hooked up on the solenoid.

you are likely getting an overboost code, that is why its falling on its face.

:stupid:
 

typhooey

New member
Re: shutting down

I figured as much cause when the motor was done I suspected something looked different but didnt realize it until the motor was broken in and did a couple of launches.
 

SeattleSy#1255

Category 5 Conservative
Re: shutting down

typhooey said:
I figured as much cause when the motor was done I suspected something looked different but didnt realize it until the motor was broken in and did a couple of launches.

can you explain what you mean here, i'm lost.
 

typhooey

New member
Re: shutting down

had the motor done over and when it was reinstalled my friend he crossed the vac lines at the turbo!
 

syntax

Member
Re: shutting down

dont you have an aftermarket boost guage? is it showing over 15 at any time? If you dont have a guage this is your first problem as the stock one isnt worth anything, sounds like you have an overboost problem.
 

typhooey

New member
Re: shutting down

I had it on the datamaster and it was perfect even though I have a stock boost guage.
 

SeattleSy#1255

Category 5 Conservative
Re: shutting down

the overboost problem is related to the chip, not the selenoid. I you are getting solid boost control on datamaster, then i'm not sure why you are wanting to change the selenoid.
 

SeattleSy#1255

Category 5 Conservative
Re: shutting down

no its normal for the stock chip. Gotta exceed 195 KPA MAP for at least
2 seconds.
I don't know what build you got, but if you have a built motor, your stock chip is going to hold you back.

CODE 31
TURBO WASTEGATE OVERBOOST


Circuit Description:

On turbo charged engines, the exhaust gases pass from the exhaust manifold through the turbocharger, turning the turbine blades. The compressor side of the turbocharger also turns, pulling air through the air filter and pushing the air into the intake manifold, pressurizing the intake manifold.
The wastegate is normally closed, but opens to bypass exhaust gas to prevent an overboost condition. The wastegate will open when pressure is applied to the actuator, and is controlled by a wastegate control solenoid valve pulsed "ON" and "OFF" by the ECM.
Under normal driving conditions, the control solenoid is energized all the time which closes "OFF" the manifold pressure to the wastegate actuator. This allows for a rapid increase in boost pressure. A boost increase will be detected by the MAP sensor, and the ECM will pulse the wastegate control valve. Manifold pressure will then be allowed to pass to the wastegate actuator, and the actuator will open the wastegate.
This will prevent an overboost condition on heavy acceleration. As boost pressure decreases, the ECM closes the control valve and the wastegate actuator pressure bleeds "OFF" through the vent in the control valve. If an overboost does exist as indicated by the MAP sensor, the ECM will reduce fuel delivery to prevent damage to the engine.

Test Description:

1. A Code 31 will set when the manifold absolute pressure exceeds 205 kPa of boost for two seconds, and a Code 33 has not previously been set. Code 31 will set, but the "Check Engine" light will stay "ON" only while the overboost exists. The light will stay "ON" for 10 seconds after the condition exists and then go "OUT."
An overboost condition could be caused by:
* CKT 471 shorted to ground
* A sticking wastegate actuator or wastegate
* A control valve stuck in the closed position
* A cut or pinched hose
* A faulty ECM
* An extremely dirty air filter

With ignition shut "OFF," the control valve solenoid is open.

2. After the 103 kPa (15 psi) is applied to valve and then the pressure source is removed, the actuator should slowly move back and close the wastegate. If the pressure does not bleed "OFF," the vent in the control valve solenoid could be plugged.

3. With the ignition "ON" and the diagnostic terminal grounded, the control valve solenoid should be energized. This closes "OFF" the manifold to the wastegate actuator.

4. Check the electrical control portion of the system. With key "ON" and engine not running, the solenoid should not be energized.

Circuit Description:

If the level of coolant in the charge air cooler (CAC) is low, the turbo boost cut-out relay will shut off all power to the wastegate solenoid. This will open the wastegate to bypass exhaust gas and lower the boost. The "LOW TURBO COOLANT" lamp will remain "ON" until coolant is added.
 
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Big Mike

New member
Re: shutting down

What fuel pump are you running? How new is your fuel filter? I know of a truck that had a problem like yours full tank/half tank it did not matter, it fell on it's face and then took off. The fuel pump was changed to a 340M with Racetronix wire harness and the problem went away.
 
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