interesting boost controler problems

[SVOeric]

I decided it was about time to turn the boost up a little on my 86 SVO... (been running at 9 psi durring break in)

So I flipped the switch, and nothing happened.. humm, I thought, must be a bad switch, so I tested the switch on the fog lights, and it was working fine.

Then I figured I would test the voltage at the boost controler itself... So I checked with the key on, and had 12 V on the hot side, but no ground (purple wire)

Now I went back to the wiring under the console, and figured it had to be something there.

I went through both my manuals (Haynes & Chiltons), and both of them have NOTHING on the wiring of the boost controler, except the Chiltons actually said there was a switch.

I can't find a fuseable link anywhere (except on the hot side, and that is in the engine compartment)

So here is what I have traced down so far -- There are 2 relays under the console, one green, the other black.  the purple wire runs out to the boost controler,(through the black relay)  while the yellow /red stripe runs to the computer. (through the green relay).  There is a resistor, that comes into the black relay, I have tested it, and it seems ok..(it is a resistor to ground, and cuts 12V down to 5V)

When flipping the preimum switch, I can hear the black relay click, I can't hear anything out of the green one.  I'm thinking the green one may be bad ??

Abyone got any experience messing with this ??

I was planning on using a aftermarket boost controler, but I wanted to keep the stock boost controler hooked up, and still use the premimum/unleaded switch, and basically switch back to the original boost controler (with no power to it) when the switch was kicked on normal (for when I let my wife drive the car, or for lack of traction problems) i could drop back to 9 pis.-- So I still need this part to work

 

[svobud]

how bout the fuse that's located under the center console?

As for keeping the stock bcs as well as running an aftermarket adjustable valve together....sounds like a waste of time. The stock BCS are known for problems (ie: bad spring for one)...especially with age/time.

I did see an aftermarket that was adjustable from inside the car (few years back)....so that's an idea. Just manually cut the boost back while driving - or parking it.

[SVOeric]

I searched for that fuse for a long time, I can't find one  I know it is suposed to be there..  I have the console completly out, and all the wiring for it laying in the passenger side floor board. 

The only thing I can find that vaugly looks like a fuse is a resistor (it says resistor right across the red rubber)

At this point, I am thinking about hooking up the unleaded/premimum switch to a jumper wire that changes the mode on the computer (that way I can still run cheap gass if I need to??) -- and put in a aftermarket boost controler.

The setup I saw  for the boost controler that will change via switch was basically 2 seperate boost controlers, with a servo that changes between the 2..  I would still need a second boost controler for the low boost, and the stock one @ 9psi would work OK for that, at least until I get something better.  -- If there is one out there that will do it without using 2, I would be HAPPY to get rid of the stock one!

[SVOeric]

I took a pic of the wiring .. all pulled out.  If anyone has any ideas on where the fuse might be,  please point it out to me...

 

 

[svobud]

I don't see it. It's usually right under the ashtray. Have you looked under the radio?

[SVOeric]

I just climbed under the radio -- almost literally -- the only fuse I found was for the radio. (I know, cause I just put it in.

I can't find a fuse anywhere...

Know what color wires it is on ??

 

[svobud]

Originally posted by SVOeric


Know what color wires it is on ??

 

no...I have a pretty good memory, but not that good.

[jhawk]

www.quickresponse.us has a two stage boost controller install on an svo.

[svo1fast4]

does this help new pic better to read

[svo1fast4]

or this different pic

[SVOeric]

jhawk -- yea they are talking about doing exactly what I was talking about... using the stock bcs for low boost, and the adjustable for high boost. -- it's easy to plum, and uses the existing stuff, so it's not real expensive, and can look stock.

 svo1fast4 -- That might help, but they are just a bit hard to read.  Which manual are those out of?

Thanks!!!

Bud -- yea -- they say the memory is the first thing to go -- thanks

[svo1fast4]

i posted new pictures easier to read i hope
they are from the 1984 shop manual supplement for the svo

[SVOeric]

I checked them out, still pretty hard to read.. I'll look harder at them ina few ---

The 84-85 SVO's had a boost controler module the 85.5, and 86's don't, so I think the wiring in your book may be different than what I have.

The boost controler module may have replaced the 2 relays that I have.

I'll dig into it farther this week and decide what I am going to do with it.

[svo1fast4]

ok i can read them fine on my pc with IE 6 but it may be different on your pc

[SVOeric]

I have the same -- IE6

The top pic does help to tell me where to look for the fuse.. it looks like it is above the 2 connections to the console. Mine has wire loom on the wires above the connectors, maybe the fuse has sliped up inside the loom, and I haven't seen it yet.

The bottom pic does show the boost controler module, that I dont have, but hopefully there is enough there to help me chase down some other stuff.

I'll tear into it one night this week... I got soooo much stuff to finish before the reunion, I am going to be BUSY BUSY BUSY!!!