Aneroid Diaphragms.
Posted: Fri Jun 22, 2007 5:56 pm
My truck has had a serious gap betwen on boost and off for a few years now.
So last week I pulled the aneroid on the fuel pump apart to see if it could be adjusted to help.
I found the rubber diaphragm in there was worn to holes completely around the outside. The reason for the on-off response was it taking full boost to give the engine more fuel, with it getting virtually nothing before then.
If you've got a factory turbo engine (or an aftermarket with an aneroid) then it's easy to check.
Look for the air line that goes from the intake manifold to the fuel pump, pull it off the manifold and blow down it. If it leaks then it needs looked at.
On an inline fuel pump they're easily unbolted, so cost to fix won't be that high. Mine was $100 for the parts. Rotary pumps I'm not sure of.
So last week I pulled the aneroid on the fuel pump apart to see if it could be adjusted to help.
I found the rubber diaphragm in there was worn to holes completely around the outside. The reason for the on-off response was it taking full boost to give the engine more fuel, with it getting virtually nothing before then.
If you've got a factory turbo engine (or an aftermarket with an aneroid) then it's easy to check.
Look for the air line that goes from the intake manifold to the fuel pump, pull it off the manifold and blow down it. If it leaks then it needs looked at.
On an inline fuel pump they're easily unbolted, so cost to fix won't be that high. Mine was $100 for the parts. Rotary pumps I'm not sure of.