Hi all, I am in need of some advise and some pointers in the right direction. So I have a overboost issue, it will pull in 4th and 5th up to around 3k then limp. I've had the car plugged in, and egr was stuck open slightly, so I blanked egr off at the cooler side as I thought it was unmeatered air that could be the issue. At the same time I decided to pull the exhaust pipe off on hot side and use Mr Muscle. At first the actuator was stiff, but after a couple of hours of spraying and moving arm, it became much easier to move. Once all back together, took for a spin, no limp, thought I cracked it. A month down the line and yesterday whilst climbing a hill in 4th, hit 3k rpm and limp again. Now I do have a buzzing noise coming from vacuum solenoid, I'm thinking this could not be helping. I have the mooing noise when I cut ignition too. Could someone advise, I'm getting a little fed up of chasing my tail. Tia 😊

Search my post on the same topic for my experience and solution.

Thank you for the info, I read your topic, I must say I was concidering changing the actuator for good measure. Is this a big job would you say? So I shouldn't be too worried about the vacuum solenoid block for the moment. 

 

Not a big job just awkward working from underneath.

 

Before starting the job ensure you can manually move the actuator from stop to stop, you should feel positive movement as the rod and VNT mechanism moves, if it doesn't snap back to the fully extended stop (low boost position) and you can move it further by hand the actuator return spring is worn/broken or the actuator rod maladjusted.

 

Apply good rust penetrant to the 2 actuator mounting bolts the day before and use a good fitting tool, not so important for the actuator rod as it and the 2 nuts are stainless steel.

 

You also might want to check the vacuum solenoid block for contamination, simply pop off the hose cap.  You could try flushing anything not air out of the block using brake clean aerosol and compressed air to dry (be gentle).  If the hoses are contaminated disconnect the lower end(s) before flushing through.

 

Although you could use the adjustment location on the original actuator (mark it) on a new fitment it's best to set a new actuator using a vacuum gauge to prevent future boost issues.  IIRC actuator should reach maximum boost stop at -16 inHg/410 mmHg.

Thank you for all your help. I shall have a look this weekend, I shall, whilst there to give another dose of Mr muscle just for good measure... I'm sure some carbon must be stuck Good as the previous owner only used the car for around town and just got coaked up in soot.