hey heres the problem... my car has had horrible boost problems lately. When I'm boosting 'well' it goes up to about .7~.8 bar and drops and builds pressure all the way down to .5.. thats when the secondary kicks in and stays at around .6 bar up to the limit.. now I've tried to figure a trend for this problem but I've had no luck... heres what I got
1) disconnected Pressure regulator hose (#30 on the diagram) or a disconnected Fuel pressure regulated hose (#37 on the diagram) its either one of those two I can't tell... the hose was off hanging above the tranny behind the engine, seems like I have to move the throttle body to get to it... yet I talked to a mechanic and he said that the Fuel pressure regulator connection is for cold starts?? or..
2) When I was putting my pre-cat back on (mistake) I accidentally split off the wire from the 02 sensor, I soldered it back on and it seemed to work fine for a few months.. yet I don't know if the connection is holding up... anyone think it could be the culprit?
3) bad turbos? they have only about 30k on them.. but anything can happen...
4) clocked pre-cat?? when I had my DP on it seemed like turbo lag was gone.. but now that the pre- cat is back on.. you guys think this could this clogged pre-cat could cause this problem?
Any other ideas? it seems like sometimes the boost is 'effective' and other times it just bouces up and down till it drops off... the bouncy boost LESSENS n pretty much goes away when I'm in higher gears (4 n 5), yet its at its worse in first and second... any help is appreciated thanks.

 

any any ideas...?

 

I think your reading into this to much. Look into the turbo hoses one mabe split slightly and only leak under higher pruressures had mine do this. I got real jummpy boost. Couldn't get full boost ever.

Try something like this
http://www.awe-tuning.com/pages/shar...ssure%20tester

Made mine from Home Depot for like $5
Worth a try before you spend big money.

Pm me for any more info if you need

Good luck

 

Codaxx is likely right, you have a hairline split in a vacuum line or the coupler, although inaudible.
You'd throw a code if the O2 sensor connection was split. Bad turbos would chatter and make noise also, if not puke oil/coolant. Pre-cat is another possibility but relatively a rare occurence. Check your hoses and your y-pipe coupler to start with and let us know.

 

cracked porcelin on rear rotor spark plug.. fixed and now it runs awesome, no more BOUNCING