The scenario....

Whilst out mapping my car with karl we noticed the peak boost and boost held was getting gradualy lower and lower (starting @ 22psi peak / 21 ish held down to 20 peak / 17ish held). I sent my exhaust housing away to be checked on the basis that the wastegate arm was twisting under load/heat but it seems this is not the case.

The problem may be resolved by fitted a new -31 Actuator, but this has not been tested yet. I guess my reason for posting was to see if anyone else has had this problem, and if so, how did you resolve it. Hopefully the new -31 will sort it but if not, any ideas as to what else could cause this to happen?

T34 / EFi L6 Webber / 1.9cvh btw

 

Air leak?? Hole in a hose/intercooler etc?

 

That was my instant reaction Christian, but the drop in boost seemed to be far to precise for an air leak which would not get gradualy worse or would it? My train of thought is that it would either leak or not and the effects would be the same every time? Are there any knowns fualts with the EFi inlet?

I'm going to have the intercooler pressure tested as it has taken a knock at some point. Just want to get to the bottom of this ASAP lol.

 

Unless the hole is growing in size. May have started out as a pin-prick sized hole in a weld and gradually opening up.

 

Sounds like your flux capacitor solenoid has gone weak

 

Thanks for your advice mate, if it is the cooler hopefuly it can be welded up.

 

My held boost is different every time i drive my car - one of lifes wonders I think

Hope you get yours sorted, been away for far too long now Dan

 

Well it aint the intercooler, had that tested and its fine. Hope the new -31 sorts it or this is gonna be a big headache!

 

You sure it isn't just pressure drop over the intercooler?

 

its not the tail off tony, ie difference between peak and held. Its the fact that every few runs we did whilst mapping it the peak and held values would be lower.

Starting at 22 peak 21 held,
then 21 peak 19 held
then 20 peak 18 held etc etc.