Questions...on lack of boost after mods.. [Archive] - SaabCentral Forums

: Questions...on lack of boost after mods..

7th January 2004, 04:26 PM
I been able to spend a bit of time finishing off some mods on my 1992 2.3 Carlsson. I've fitted the poly bush to the gearbox and when the inner wing was off modified the airbox by removing the snorkle and putting some large holes on the back edge of the cover. I completed fitting the water injection kit, and utilised the washer bottle from a 91 Carlsson which fitted on the nearside inner wing, its handy when I have spare cars available! I had to move the fuse box forward as per the older car and used the older cars fuse box bracket also. This makes it look like a factory fit and means I can run 50% methanol mix safely. I also retain the low level switch.
However when I took the car out for a test run I noticed it wasn't boosting as high as normal, ( used to pull 1.6 dropping back to a steady 1.3 bar easily). I disconnected the mbc and reverted back to auto but it would only run to 0.5 bar and if I wasn't WFO the boost would start hunting between 0.4 - 0.5 bar.
All vac pipes are okay and now I've put the mbc valve back on I've wound it up a wee bit but whilst it spikes at about 1.5 bar it rapidly falls back to 0.7 bar and stays at that figure in 3rd up to the redline. If I floor it in 5th it spikes at 1.5, drops to about 1 bar then drops to 0.9.
The water injection is set to come on at 0.8 bar and is on 100% water at present.
I'm stumpted on why the boost has fallen off so much since doing these mods.
Any ideas???

8th January 2004, 05:17 PM
I would go back and double check everything, did you happen to disturb a ground or a connection someplace?

9th January 2004, 11:50 AM
is your water injector too big so there is too much water being sprayed in

13th January 2004, 07:16 AM
Found out the problem, next day smoke started pouring out of the exhaust...checked turbo for play...6mm of horizontal movement. Exh and compressor blades wrecked. Luckily I have a spare car and built up a good spare to fit. I'm having to back off loads on my MBC valve now as boost is too much.... :cry: :wink: