What's controlling boost on my car?

[twoqu]

Looks like I made an error on wastegate cap ID! Please see here:

http://www.s2forum.com/forum/showthread.php?p=467031#post467031

The "adjustable" one in the pics is actually a 20V one that has been unglued to allow adjustament. The others must all be 10V!

[JP]

I'd check whether your N75 valve is working properly. Remember even with it disconnected if it is not sealing properly it will be bleeding of boost. LIkewise a slight split in the hose where it connects to the wastegate as these get brittle through the years.

Best thing to do is keep the N75 plugged in and bypass it by running a 7-8mm hose direct from the turbo boost nipple upto the wastegate. Then check what boost you are making. If it solves it then look for splits in the original hose and if there is none and it clamps tight at all the joints get yourself a new valve.

hth JP

[AndyP]

I'd check whether your N75 valve is working properly. Remember even with it disconnected if it is not sealing properly it will be bleeding of boost. LIkewise a slight split in the hose where it connects to the wastegate as these get brittle through the years.

Best thing to do is keep the N75 plugged in and bypass it by running a 7-8mm hose direct from the turbo boost nipple upto the wastegate. Then check what boost you are making. If it solves it then look for splits in the original hose and if there is none and it clamps tight at all the joints get yourself a new valve.

hth JP

Still getting this issue even with the new engine in. The only common componants are the ECU and the WGFV so I'll try bypassing it tonight and see what boost it gives.

[Jamo]

You want to ditch that N75 and get a decent solenoid valve as a replacement

[QuattroFever]

not the barometer gadget playing hocus pocus is it? (If the 3b has one)

Its the only thing i can think that would peg it at a set threshold other than mech. Boost.

[AndyP]

Not sure, I've re-piped it last night so the boost goes straight to the wastegate as per JP's post, I'll take it for a spin tonight and report back.

I must be the only person on the forum complaining that I can't get mechanical boost

[QuattroFever]

doh. Mech boost. Ignore above.