G
Guest
·Hi - an update on the fuel cut problems (I've started afresh so as not to make the other thread too big).
I deliberately 'kinked' the pipe containing the plastic restrictor and put a cable tie round it, essentially closing off the vent path through the solenoid. See pic
The result is NO FUEL CUT! However I noted that it wasn't nearly as powerful and the exhaust note was subdued (although the turbo SSSshhhhhhhhhh on full boost seemed more pronounced). As I'm still waiting for the boost guage I borrowed one again today just to see what would happen - previously when it was fuel-cutting it surged to 1.3bar and after a second or two it dropped to 1.0bar. With the kinked pipe it is now going directly up to 1.0bar and sitting there (ie. no surge). From HH6's explanation the surge is due to the plastic restrictor in the path to the boost control solenoid. Now I've closed the path entirely I expected this to happen.
Questions;
I assume if I fit the bypass valve I'll get SOME surge back?
Do I want this pressure surge? What purpose is the surge there for?
Why does it seem slower if the constant post-surge pressure before and after I kinked the pipe is the same at 1.0bar?
I assume that the ECU shuts the solenoid to reduce boost, so does the plastic restrictor on the way to the solenoid cause the fuel cut?
I think until I refit the bypass valve I'll leave it this way - seems slower, but obviously much safer.
I deliberately 'kinked' the pipe containing the plastic restrictor and put a cable tie round it, essentially closing off the vent path through the solenoid. See pic

The result is NO FUEL CUT! However I noted that it wasn't nearly as powerful and the exhaust note was subdued (although the turbo SSSshhhhhhhhhh on full boost seemed more pronounced). As I'm still waiting for the boost guage I borrowed one again today just to see what would happen - previously when it was fuel-cutting it surged to 1.3bar and after a second or two it dropped to 1.0bar. With the kinked pipe it is now going directly up to 1.0bar and sitting there (ie. no surge). From HH6's explanation the surge is due to the plastic restrictor in the path to the boost control solenoid. Now I've closed the path entirely I expected this to happen.
Questions;
I assume if I fit the bypass valve I'll get SOME surge back?
Do I want this pressure surge? What purpose is the surge there for?
Why does it seem slower if the constant post-surge pressure before and after I kinked the pipe is the same at 1.0bar?
I assume that the ECU shuts the solenoid to reduce boost, so does the plastic restrictor on the way to the solenoid cause the fuel cut?
I think until I refit the bypass valve I'll leave it this way - seems slower, but obviously much safer.