Can anyone shine some light on this problem?
It is a 2.4 Turbo with mechanical inj. pump and manual gearbox.
When the revs are between 1500 and 1950 and held steady, the engine pulses. This is being caused by the butterfly valve in the venturi system on the air inlet side opening and closing. Once the revs rise above 1950 the valve remains in position and things smooth out.
I have checked as far as I can that the vacuum pipes are correctly positioned but there is not a great deal of info that I can find to show the correct position for all the vacuum piping.
When the truck was bought the pipe to the venturi was removed and blocked so I suspect that it is a long standing problem.
Also, there is a screaming noise once the turbo is on boost, we have changed turbos but it is still the same (there isn't any excessive play in either turbo). I have checked all the joints on the pressure side of the turbo and found no leaks. Any ideas as to where to look next?
Thanks in advance for any help.
Tony
It is a 2.4 Turbo with mechanical inj. pump and manual gearbox.
When the revs are between 1500 and 1950 and held steady, the engine pulses. This is being caused by the butterfly valve in the venturi system on the air inlet side opening and closing. Once the revs rise above 1950 the valve remains in position and things smooth out.
I have checked as far as I can that the vacuum pipes are correctly positioned but there is not a great deal of info that I can find to show the correct position for all the vacuum piping.
When the truck was bought the pipe to the venturi was removed and blocked so I suspect that it is a long standing problem.
Also, there is a screaming noise once the turbo is on boost, we have changed turbos but it is still the same (there isn't any excessive play in either turbo). I have checked all the joints on the pressure side of the turbo and found no leaks. Any ideas as to where to look next?
Thanks in advance for any help.
Tony
Comment