No boost/power fixed by unplugging FCV?

[Sugarkryptonite]

Hi guys

2006 Liberty

Been battling this problem for the past few weeks. Very annoying.

Randomly would have low power on the CRD, boost would be 3-4psi max, would go at maximum 30-40mph. I tried everything. New pump regulator from Bosch, new rail regulator, new MAP, checked all boost hoses, checked all wiring for any rubbing etc.

Had no codes for anything FCV related. Only thing I saw one time after deleting the codes was EGR insufficient flow. I started reading up on the EGR system and it said it could be disabled by unplugging the MAF. I tried that and no change. Then I left the MAF unplugged and also unplugged the FCV. Instantly all the power came back, but the truck smokes like crazy. I then decided to try plugging the MAF back in and now the truck runs like normal with full power and only the FCV disconnected.

I know that the FCV is used for EGR flow and shutdown, so do you guys think my EGR is clogged so the computer is closing the FCV so much it’s choking the motor? I had the intercooler hose off and the FCV was wide open with the car shut off.

 

[turblediesel]

The FCV has plastic gears inside that strip out leaving the butterfly valve stuck wherever it happens to be. You can replace the FCV or just remove the butterfly part. You can also remove the FCV completely and replace it with a bent tube from an EGR bypass kit.

 

[WWDiesel]

Best advice is to remove the butterfly plate out of the FCV. Only two small torx screws holding it to the shaft. Can be removed in less than 30 minutes.
The small gears in the FCV operator are notorious for stripping and hanging allowing the FCV to block or limit air flow and boost from entering the intake manifold. If you are in an area where you can, it is best to totally remove all the EGR parts using a Delete Kit available from some vendors online. At a minimum you should install a block off plate between the exhaust feed tube and the EGR valve. Plate pictured below. It can be made out of any thin sheet metal even the lid from a soup or vegetable can.

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[Sugarkryptonite]

Best advice is to remove the butterfly plate out of the FCV. Only two small torx screws holding it to the shaft. Can be removed in less than 30 minutes.
The small gears in the FCV operator are notorious for stripping and hanging allowing the FCV to block or limit air flow and boost from entering the intake manifold. If you are in an area where you can, it is best to totally remove all the EGR parts using a Delete Kit available from some vendors online. At a minimum you should install a block off plate between the exhaust feed tube and the EGR valve. Plate pictured below. It can be made out of any thin sheet metal even the lid from a soup or vegetable can.

You must be registered for see images attach

Thanks!