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Gregs900
02-25-2011, 08:25 PM
I am getting 8 lbs with or without the swith on. Pulled the console and do not have a clue as to what it looks like or exactly where the fuse is. Can someone help with what it looks like.

NotBud
02-25-2011, 08:59 PM
What year is your SVO? Only the 84's and early 85's have that fuse - if your car does not have the Boost Control Module, it will not have this fuse.

On the 84 it's taped into the harness behind the right side of the radio (unless it's been mucked with already). If the radio is out, it's right here (see pic). You can also reach it from the passenger (right) side front of the dash, just beyond the the console..

Gregs900
02-25-2011, 09:29 PM
Thanks for the quick reply. I have a 1984. When I pulled it apart today I saw that fuse and assumed it was for the radio. I checked it and it looked fine but maybe I should still replace it. If it is good then I wonder what else would keep the boost at 8 lbs. Hoses leaking maybe. I did notice that the turbo is a newer one that has the capability to be water cooled due to having fittings on it. Could that be limiting boost? Any sugestions appreciated.

NotBud
02-26-2011, 11:31 AM
There is a three-wire connector at the large silver box on the front of the right front shock tower (It's cast into the box Duraspark). That is the BCM (boost control module). Unplug that 3-wire connector and see if there is +12VDC there with the ignition key on (red to black wire). If yes, the fuse and circuit are good. Move on.

Look to see that the three-wire connector is plugged into the BCM box and that the two-wire connector is connected to the BCS (boost control solenoid). If they are (or were), then run the KOEO test and check for proper cycling of the BCS.

As a general rule, leaking hoses will result in higher boost levels since the controlled leaking is how the stock system increases pressure. Pressure must reach the wastegate diaphragm to open it.

Lastly (or firstly), check how much pressure the wastegate diaphragm needs to open the flapper valve. Stoclkis to have 0.015" of flapper movement at 10.0 PSIG (*/- 0.5). With age and time of exposure ot the exhaust heat the diaphragm spring gets weaker, thus opening at a much lower pressure. If it opens at less than 9 PSI, replace the wastegate diaphragm assy,

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8T6 SVO
02-26-2011, 01:19 PM
There is a three-wire connector at the large silver box on the front of the right front shock tower (It's cast into the box Duraspark). That is the BCM (boost control module). Unplug that 3-wire connector and see if there is +12VDC there with the ignition key on (red to black wire). If yes, the fuse and circuit are good. Move on.

Are you talking about this box (see below). I know nothing about these because I have only had a 1986 model SVO which these "duraspark" boxes never came with.

I have no need for this part. I thought it was for an early turbo motor - 1979 ish. If someone can use this, send me a PM.

Gregs900
02-26-2011, 03:36 PM
Thanks for all your help and problem is solved and I am getting about 15 lbs boost. It feels great to drive it. This site has been a great help not only from everyones direct input but in reading old posts. I plan on studying up on the 2.3 turbo engine manual at forced 4.

NotBud
02-26-2011, 03:56 PM
Are you talking about this box (see below). That looks like a real DuraSpark box form a late 70's car. The BCM I'm referring to was not used on the 85.5/86 SVO.

The 84/85 BCM/BCS looked like this pic. Note that the module (box) only has (1) two-wire and (1) three-wire connector in it.