Just got it back after and engine out job to replace the turbos after the driver side one siezed. Seems to have the power back but the boost gauge no longer works it just goes to the middle when switched on and the engine is also hunting at tickover. If I detach the vacuum pipe that goes from the balance pipe to the gubbins on the firewall beside the brake servo and put a finger over the balance pipe connection on the plenum it ticks over and runs beautifully.

 

Its as if its got an air leak but it hasnt.

 

If I blow up that small hose to the gubbins where I suspect the boost guage sensor also is I get no air leaks. If I suck when the engine is running the engine suddenly runs rough again just like when its connected. It seems the vacuum at idle is affecting some control system that is causing the rough running. PCV maybe? and the non working boost guage - is there a connection?

 

Has the mechanic connected these small vacuum hoses up wrongly or is something else going on here? All ideas gratefully considered.

Is the one-way valve on the clutch servo the wrong way round ....

Should have mentioned its an auto.

Just got it back after and engine out job to replace the turbos after the driver side one siezed. Seems to have the power back but the boost gauge no longer works it just goes to the middle when switched on and the engine is also hunting at tickover. If I detach the vacuum pipe that goes from the balance pipe to the gubbins on the firewall beside the brake servo and put a finger over the balance pipe connection on the plenum it ticks over and runs beautifully.

 

Its as if its got an air leak but it hasnt.

 

If I blow up that small hose to the gubbins where I suspect the boost guage sensor also is I get no air leaks. If I suck when the engine is running the engine suddenly runs rough again just like when its connected. It seems the vacuum at idle is affecting some control system that is causing the rough running. PCV maybe? and the non working boost guage - is there a connection?

 

Has the mechanic connected these small vacuum hoses up wrongly or is something else going on here? All ideas gratefully considered.

 

 

hes connected them up incorectly

 

look in corner where small fusebox is check lines coming from there,i should imagine, the mechanic which is easily done, has run either the egr pipe that is just below master cylinder to the balance bar,and the vacuem for the gauge to the egr, hence why you have no gauge reading, either that or the air feed that is bolted to the plenum, above wastegate actuator which has 2feeds check the white dotted hose is on the top and the plain one at the bottom!

 

il find a pic for you

Greg

 

I think you've got it. I found the gauge sensor and there was no vacuum at it with the engine running. I swopped tubes with the other one that does go to the balance pipe and low and behold gauge works and engine idles fine. It worries me that there doesnt seem to be any suction on the other egr? hose - does egr only work when there's positive pressure ot some other condition?

 

The mechanic marked tube ends with coloured paint but he must have swapped it at the other end.

Greg

 

I think you've got it. I found the gauge sensor and there was no vacuum at it with the engine running. I swopped tubes with the other one that does go to the balance pipe and low and behold gauge works and engine idles fine. It worries me that there doesnt seem to be any suction on the other egr? hose - does egr only work when there's positive pressure ot some other condition?

 

The mechanic marked tube ends with coloured paint but he must have swapped it at the other end.

 

i can only assume the lack of vacuum from the egr, is the hose has come off from the egr-back of engine,best way is to run some silicone direct from egr to port, rather than nissans over engineered routing of the metal pipe under the plenum glad you sorted it, couldnt find a pic of the balance pipe, but you know these cars anyhow, so assumed you would sort it

 

greg

magic