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Discussion Starter #1
Hi, I have recently managed to get hold of a complete wiring harness from a 90 turbo. it includes the wiring to the APC, the APC and the solenoid valve, as well as the knock sensor...(should be on the plane next monday :cheesy: )
the thing is, i understand i would need more items before it's complete. my vert's an LPT, so what do i already have??

1. pressure transducer?
2. overpresure switch?

i've recently fitted the orginal IC, so that's not an issue...

anything else i may need??

sorry to be a bother, but i tried searching, but couldn't find the info i really needed...

btw, i have checked at http://www.900aero.com/

tks
 

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You need the pressure transducer. You don't really need the overpressure switch and, anyway, there is none on a '90 (Jetronic manages overpressure cut-off by using the air mass meter voltage).You need a wiring diagram of the APC system; it may be on 900aero.com.
 

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I'll second that ... the pressure transducer tells APC what the manifold pressure is. You need that. The overpressure switch would be bypassed anyway (in your boost gauge project) ... you don't need that.

Have a look at http://www.900aero.com in the DIY section and click 'LPT to FPT' ... that will give you a good guide.

Essentially, APC relies on a number of inputs - RPM, pressure and knock. For the LPT upgrade, you need to fit the APC box, a knock sensor (taking care to offset it from the block by the correct angle), a pressure transducer (see above) and a wastegate solenoid valve. The wiring is another matter - check the 900 Aero pages.
 

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Discussion Starter #4
Orca said:
I'll second that ... the pressure transducer tells APC what the manifold pressure is. You need that. The overpressure switch would be bypassed anyway (in your boost gauge project) ... you don't need that.

Have a look at http://www.900aero.com in the DIY section and click 'LPT to FPT' ... that will give you a good guide.

Essentially, APC relies on a number of inputs - RPM, pressure and knock. For the LPT upgrade, you need to fit the APC box, a knock sensor (taking care to offset it from the block by the correct angle), a pressure transducer (see above) and a wastegate solenoid valve. The wiring is another matter - check the 900 Aero pages.
i think i will be getting the APC, wiring harness, solenoid and knock sensor. so i'm probably on the way there. still missing the pressure transducer though (i think it's a device with the red knob on top, and usually fixed next to the APC??)
as for the knock sensor, can you elobarate what you mean by the correct angle? i know it is very sensitive, but what is the correct offset??
i'll definitely check 900aero again when my items are complete. tried to copy and paste on a document so i can print it out, but it was copy-right protected ;oops:
tks, will post again when my items are complete
cheers
 

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peckhs said:
i think i will be getting the APC, wiring harness, solenoid and knock sensor. so i'm probably on the way there. still missing the pressure transducer though (i think it's a device with the red knob on top, and usually fixed next to the APC??)
Ah, no ... the pressure transducer is also inside the car, next to the overboost fuel-cut switch. It looks very similar. The device next to the APC box with the red cap is a pressure relief valve for the cruise system. It has a vacuum pipe which tees into the main cruise control vacuum line (the wider bore pipe ... about 5mm?) ... on our LPT cars, there does not seem to be the necessary power connection available in the inner wing. I'm going to run into this problem, too ... can someone advise, please?
 

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Discussion Starter #6
Orca said:
Ah, no ... the pressure transducer is also inside the car, next to the overboost fuel-cut switch. It looks very similar. The device next to the APC box with the red cap is a pressure relief valve for the cruise system. It has a vacuum pipe which tees into the main cruise control vacuum line (the wider bore pipe ... about 5mm?) ... on our LPT cars, there does not seem to be the necessary power connection available in the inner wing. I'm going to run into this problem, too ... can someone advise, please?
you maen there's no power connection for the pressure transducer? can we tap it from the speaker?? or you are meaning something else...
btw, i'm short of a pressure transducer... anyone got spare??? :cheesy:
 

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yeah ... you need pressure transducer
I fitted my APC just in factory fasion, i.e., transducer behind the knee bolster ... don`t remember the wiring thing, I think I fed it from the fue box ... check the wiring diagram in Bentley ...
 

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Discussion Starter #8
it's has arrived!!!!

well, my items (less the pressure transducer :cry: ) has finally arrive.
I managed to get hold of the complete wiring harness from a 90 turbo, and i hope it is compatible with my 92 vert...

1. the wiring harness.... complete..

looks a mess with the many connectors and cables, but will sort it out when i compare the one in my vert

2. the APC

the APC has the number 7566599 on it, and I wonder what spec it has?? anyone can identify the box?

3. the solenoid with mounting bracket and hoses

I'm wondering which connector it should be connected to.. i counted and there are 6 probable connectors
 

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Discussion Starter #9
4. the knock sensor


i figured out the connector to the APC and knock sensor..





so that's not a problem... btw, the APC got a 25pins connector..
 

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Discussion Starter #10
but i have a problem with 3 connectors in the fuse box...



i think they have came off from the proper slot... a closer look...



a close up of one of the connector..



and the slot



i believe the "wings" on the side of the connectors are to hold them in place in the slots, the problem is, i can't seem to be able to push the connectors into the slot as the "wings" are in the way...
has anyone encountered this problem? seems the only way is to insert the connectors from the top, but to do that i'll have to remove the wires!!
can anyone help??

another thing... i can't seem to find the pressure sensor in the EPC.. does it have another name? part number?? i will need it for this project...

thanks
 

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According to the 900 Aero website, your APC box is the 160 BHP specification. The good news is, it's just a "pot tweak" to bring up to 175 BHP. Move F from 11.9 KOhms to 12.4 KOhms and P from 96 Ohms to 201 Ohms.

I've no idea what the three connectors are about. Hope someone else knows.

I did spot a number of other connectors ... I think one of the two hole connectors goes to the cruise pressure relief valve we were talking about - the red capped thingy. Another will be for the solenoid valve that controls the wastegate. Have a good read through: http://www.900aero.com/main/diy_main_lpt.htm ... there's some good information in there.

Here's the pressure transducer, BTW:



... it's the one on the left with one vac pipe coming out of it. The other device is the overboost fuel-cut. See it has two ports here ... our LPTs only have one port, but you can bypass that by not running a vac line to it and running it straight to your boost gauge.
 

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Discussion Starter #12
Orca said:
... on our LPT cars, there does not seem to be the necessary power connection available in the inner wing. I'm going to run into this problem, too ... can someone advise, please?
orca, i believe 900aero site has solved this issue...(i can't copy as it's protected)
 

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Orca said:
That's odd ... I don't seem able to find the pressure transducer in the EPC, either :( I wonder if 9342064 is actually the pressure transducer and the fuel cut-off is actually not listed?

I've found a couple of other good links relating to APC installations:
http://hjem.get2net.dk/bengaard/apc-syst.htm
http://web.archive.org/web/20010124085700/http://www.teleport.com/~bertram/volvoapc/

... they apply to Volvo installations, but give a good set of guidelines for installation on "any car".
i think it is also called the boost sensor and/or turbo over pressure sensor

this pic from the saab site, part number 9342064

we couldn't find it probably cos it's a device with many names....:cheesy:

but it is listed as obsolete... maybe it has been replaced by another item?? i don't know...
 

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It's called "Pressure sensor" according to the EPC. You should be able to get it from the junk-yard...!
Daniel.
 

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well, if I was you ... I wouldn`t change whole wiring ... unless your car and the spare wiring is the from the same MY and modification car ...

For the APC you really dont need anything to be wired into the cabin (except brake pedal switch that cancels APC - you can ditch that function anyway). You need some juice from the fuse box, that true. But it means runing only one single wire from the fues box. Pressure transucer you can fit near the APC itself, so no wiring into the cabin.

That way you need to take that part of wiring connecting APC <-> knock sensor/APC <-> solenoid without modification ...
Then open up the part of wiring going into the fuse box and take just wires for pressure tranducer, 12V power supply and brake cancel function.
Ditch the brake cancel wire, connect pressure transducer to the wiring and take the 12 V wire along your existing wiring inti the fuse box ...
Than you need also to identify RPM signal wire and connect to the ignition signal amplifier.

That way you will not be entering your existing and functioning wiring ... you will not open up your car to potential problems that might be caused by possible incompatabilites between the two harnesses ...
I wouldn`t disturb my wiring to such an extent `coz you never know

Even if you decide to have brake cancel and pressure transducer in the cabin, it means simply runing 3-4 wires brom fuse box into the cabin throug the spare holes in the firewall ...
 

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Discussion Starter #17
KurBads said:
well, if I was you ... I wouldn`t change whole wiring ... unless your car and the spare wiring is the from the same MY and modification car ...

For the APC you really dont need anything to be wired into the cabin (except brake pedal switch that cancels APC - you can ditch that function anyway). You need some juice from the fuse box, that true. But it means runing only one single wire from the fues box. Pressure transucer you can fit near the APC itself, so no wiring into the cabin.

That way you need to take that part of wiring connecting APC <-> knock sensor/APC <-> solenoid without modification ...
Then open up the part of wiring going into the fuse box and take just wires for pressure tranducer, 12V power supply and brake cancel function.
Ditch the brake cancel wire, connect pressure transducer to the wiring and take the 12 V wire along your existing wiring inti the fuse box ...
Than you need also to identify RPM signal wire and connect to the ignition signal amplifier.

That way you will not be entering your existing and functioning wiring ... you will not open up your car to potential problems that might be caused by possible incompatabilites between the two harnesses ...
I wouldn`t disturb my wiring to such an extent `coz you never know

Even if you decide to have brake cancel and pressure transducer in the cabin, it means simply runing 3-4 wires brom fuse box into the cabin throug the spare holes in the firewall ...
Hi, tks for the advice... the idea initially was to get only the APC wiring harness. but the person selling the wiring harness would not sell me just the APC wiring... so now i have with me the complete wiring harness :cheesy:

I'm not very keen to replace the entire wiring harness in the first place, but i'm still pondering how best to go about doing it.

my car runs fine now, and i wouldn't want to mess things up...

cheers
 

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Discussion Starter #18
Orca said:
That's odd ... I don't seem able to find the pressure transducer in the EPC, either :( I wonder if 9342064 is actually the pressure transducer and the fuel cut-off is actually not listed?

I've found a couple of other good links relating to APC installations:
http://hjem.get2net.dk/bengaard/apc-syst.htm
http://web.archive.org/web/20010124085700/http://www.teleport.com/~bertram/volvoapc/

... they apply to Volvo installations, but give a good set of guidelines for installation on "any car".
I have finally managed to purchase a FPT's boost cut-off switch and pressure transducer/boost sensor!! :cheesy:

Now i will have to wait for them to arrive, and i will be able to start my APC upgrade :lol:

cheers
 

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Do NOT replace your car's wiring loom, thats asking for trouble. Start from the apc connector if you want, with a multimeter, identify the wires, and pull them out.
 

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philb said:
Do NOT replace your car's wiring loom, thats asking for trouble. Start from the apc connector if you want, with a multimeter, identify the wires, and pull them out.
as I already suggested ...

and if you need any advice, just ask ... I did my APC install just ~ 1 month ago ... have some fresh memmories and pics ...

Maybe worth making lpt 2 fpt thread with pics?
 
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