Project Loki - 1988 classic SAAB turbo

A place for long term threads surrounding a specific project or SAAB build for motorsports or restoration
User avatar
Geoff
Team Turbo Troll Crew
Posts: 3888
Joined: Fri Oct 20, 2006 3:31 pm
Nickname: Geoff
Number of Saabs currently owned: 6
Location: Nude Humpshire

Re: Project Loki - 1988 classic SAAB turbo

Postby Geoff » Fri Nov 07, 2014 11:48 am

Good thing to look into. It's under the dash on the driver's side, pull back the black plastic heater vent and you'll probably see it. So yeah, right next to the turbo.
It's about 1.5"-2" around, off-white plastic with a galvanized steel housing. Pressure hose going into it. Should have a wire going in and a wire going out and a spare terminal.
When the car over-boosts it cuts power to the fuel pump (or is it ECU? diagram too blurry...). If it fails I think it will cause a non-start :-)
The kind of dirty that doesn't wash off :eyebrows:

User avatar
Jordan
Site Admin
Posts: 4068
Joined: Fri Oct 13, 2006 2:38 pm
Number of Saabs currently owned: 6
Location: Vernon, CT
Contact:

Re: Project Loki - 1988 classic SAAB turbo

Postby Jordan » Fri Nov 07, 2014 1:05 pm

That is the fuel cut switch for overboost situations. It should be under the dash on the driver side. From the diagram it supplies switching power to the relay to terminal 86. So if you jump the relay (30 -> 87 & 87B) it should supply power to the injectors and fuel pump and the car should start. If it does then it is something on the switched power on the relay of the fuel pump that you correctly identified. From there it could only be a) the power coming out of the main relay, that then goes through the overboost switch into the fuel pump relay. or b) the ecu trigger to ground, which you seem to have ruled out with the ECU swap.


I think you're getting really close.

Adrian Thompson
Posts: 170
Joined: Mon Mar 12, 2012 10:14 am
Number of Saabs currently owned: 1

Re: Project Loki - 1988 classic SAAB turbo

Postby Adrian Thompson » Sat Nov 08, 2014 6:10 pm

OK, I didn't get home today in daylight to have a go at fixing anything, all I could do was have a quick look and snap a couple of pics.

First, is the circular can on the left the pressure switch, I don't feel any wires going into the back off it, but I'll have a better look tomorrow. IT's more in the center of the car than to the left though
Image

Next,is this odd connector with a red on the right hand side. What is it and should it be connected to anything? The two single connectors below it with brown leads are too the pressure switch BTW
Image

Finally this. This connector is below and to the left of the steering column. IT does not appear to be fully seated, I couldn't push it together any better tonight, I'll investigate tomorrow. Also see the yellow wire with a female connector loose, that is from the same bundle that goes into this connector. Any idea what it is and is it important?
Image
Project Loki - 88 900C - future TSD, Rallycross and track day toy

hutch
Posts: 828
Joined: Fri Apr 20, 2007 11:49 pm
Number of Saabs currently owned: 2
Location: Lancaster, PA

Re: Project Loki - 1988 classic SAAB turbo

Postby hutch » Sat Nov 08, 2014 7:47 pm

Adrian Thompson wrote:First, is the circular can on the left the pressure switch
I believe that is to open/close the HVAC vents, I'm trying to find a better picture online, but it should have an adjustment knob on the top of it like this:
Image

A quick read on another forum says that the vacuum line to the boost gauge goes t's off to the overboost switch so you may be able to trace it down from there. Since I believe you have most of the car stripped at this point I'd just take the whole dash off, it makes troubleshooting everything up there much simpler.

Adrian Thompson
Posts: 170
Joined: Mon Mar 12, 2012 10:14 am
Number of Saabs currently owned: 1

Re: Project Loki - 1988 classic SAAB turbo

Postby Adrian Thompson » Mon Nov 10, 2014 8:44 am

hutch, I'm not sure I totally follow what you're saying. I believe you are correct that that is the HVAC control, so I don't think it will affect my no start issue

I found another much smaller unit on the RHS up under the dash.

The connector I showed the other day that would not close, i did find an issue. When I pulled it apart one pin was bent sideways not going into the socket and preventing it closing. I straightened that up and the connector closed up again. Still no start though.

I really don't want to pull the dash out, but I think my next step is to start with pin one on the ECU and trace every single wire back to whatever it's connected too and check it out.
Project Loki - 88 900C - future TSD, Rallycross and track day toy

User avatar
Luke
Site Admin
Posts: 3387
Joined: Tue Sep 19, 2006 11:12 pm

Re: Project Loki - 1988 classic SAAB turbo

Postby Luke » Mon Nov 10, 2014 9:12 am

Adrian Thompson wrote:Next,is this odd connector with a red on the right hand side. What is it and should it be connected to anything? The two single connectors below it with brown leads are too the pressure switch BTW
Image


The quick check for the pressure switch is to unplug the brown leads and plug the ECU sides together to close the loop. That bypasses the switch althogether. Fun fact: The NA 900's are setup with the same brown leads but they are looped together from the factory.

DeLorean
Posts: 1193
Joined: Sat Mar 31, 2007 9:54 pm
Number of Saabs currently owned: 9
Location: Pennsylvania, Forever!
Contact:

Re: Project Loki - 1988 classic SAAB turbo

Postby DeLorean » Mon Nov 10, 2014 10:17 am

Yep, the 86-88 16V cars under dash harness is the same turbo and non turbo, the turbos just have some extra equipment under there. Get that over-pressure switch out of these. I have often seen them fail in a manner that prevents the car from starting, typically only in cold weather.
Less brake more gas!

User avatar
Geoff
Team Turbo Troll Crew
Posts: 3888
Joined: Fri Oct 20, 2006 3:31 pm
Nickname: Geoff
Number of Saabs currently owned: 6
Location: Nude Humpshire

Re: Project Loki - 1988 classic SAAB turbo

Postby Geoff » Mon Nov 10, 2014 1:17 pm

Most of your pictures are of the passenger's side of the car. You need to look on the driver's side. It is to the left of the steering column, above the heater vent, attached to a bracket. Hutch is right, follow the vacuum hose from the boost gauge and you'll eventually find the pressure switch. The pressure switch looks just like the picture Hutch posted but you can't see it because of the bracket and other components which are in the way. The bracket comes out when you remove two bolts which either have torx or 10mm heads (depending on year) at the top of the bracket.

Dead center in this picture
Image

The very top red hose in this picture is connected to it (for some reason this bracket is black, I don't think I've ever seen a black one)
Image
The kind of dirty that doesn't wash off :eyebrows:

User avatar
Jordan
Site Admin
Posts: 4068
Joined: Fri Oct 13, 2006 2:38 pm
Number of Saabs currently owned: 6
Location: Vernon, CT
Contact:

Re: Project Loki - 1988 classic SAAB turbo

Postby Jordan » Mon Nov 10, 2014 1:22 pm

And behind that is the pressure transducer, which is also almost broken, but wouldn't cause the no start, just no boost.

Adrian Thompson
Posts: 170
Joined: Mon Mar 12, 2012 10:14 am
Number of Saabs currently owned: 1

Re: Project Loki - 1988 classic SAAB turbo

Postby Adrian Thompson » Mon Nov 10, 2014 1:24 pm

Thanks guys. Picture of what I'm supposed to be looking at. I'll check tonight and also try the looping the Pressure switch leads together.
Project Loki - 88 900C - future TSD, Rallycross and track day toy

Adrian Thompson
Posts: 170
Joined: Mon Mar 12, 2012 10:14 am
Number of Saabs currently owned: 1

Re: Project Loki - 1988 classic SAAB turbo

Postby Adrian Thompson » Tue Nov 11, 2014 6:17 pm

Looped the over boost circuit on itself and still no joy. HAve to wait for day light and break out the volt meter and wiring diagram again.
Project Loki - 88 900C - future TSD, Rallycross and track day toy

Adrian Thompson
Posts: 170
Joined: Mon Mar 12, 2012 10:14 am
Number of Saabs currently owned: 1

Re: Project Loki - 1988 classic SAAB turbo

Postby Adrian Thompson » Sat Nov 15, 2014 1:33 pm

Laugh or Cry? I don't know.

Well I started again today pinning things out. I soon found I had no power to the ECU, funny I used too. Check fuse 22.....dead. OK, I wonder why, when that blew. No problem I'll change it for now.

OK, power to the ECU. Let's try it. Still no fuel pump relay firing, let's just jump that again.

Hit it.... This is the result.

https://www.youtube.com/watch?v=5-2NKow ... 7w&index=2

Let's have a look. This is the turbo
Image
Oil, oil every where.


And this is what the tail pipe looks like

https://www.youtube.com/watch?v=XOf_ms1 ... 7w&index=1

So part of me is jumping for joy that I actually got it started, but lets take stock.
1. The Fuel pump circuit won't trigger from either ECU although it works when I remove the relay and jump across there terminals which suggests it should.
2. The turbo that worked fine before I pulled out the interior has decided for some unknown reason to do it's best 1980's F1 klabamo after not having run for a year.

Why? WTF is going on. I do have another used turbo of unknown heritage in a box. Do I bolt that on, or do I either try and rebuild one of them myself or pay for a pro to rebuild one of them? And why would a turbo just die on a car after lack of use?

Also, the fuel pump relay issue? WTF, anyone have any ideas?

At least it's started, although I couldn't get it to re-start a 3rd time after the first two. At least ut was trying, I wonder how much oil has now got in the engine, do I have to pull the head off and clean it up as well?
Project Loki - 88 900C - future TSD, Rallycross and track day toy

User avatar
SwedeSport
Posts: 3021
Joined: Mon Jun 15, 2009 9:52 am
Number of Saabs currently owned: 5
Location: Pottstown, PA
Contact:

Re: Project Loki - 1988 classic SAAB turbo

Postby SwedeSport » Sun Nov 16, 2014 8:59 am

I wouldn't worry about the turbo just yet.

My daily driver smokes a bit after sitting for long periods of time.
Swedesport Motors, Apparel and Accessories for SAAB Junkies.
Http://Facebook.com/swedesportmotors
Swedesportmotors@gmail.com

User avatar
Geoff
Team Turbo Troll Crew
Posts: 3888
Joined: Fri Oct 20, 2006 3:31 pm
Nickname: Geoff
Number of Saabs currently owned: 6
Location: Nude Humpshire

Re: Project Loki - 1988 classic SAAB turbo

Postby Geoff » Sun Nov 16, 2014 10:45 am

That white smoke looks like fuel. Two potential causes I've experienced:
1) Catalytic converter flooded with fuel from all the cranking/non-start issues (usually works it's way out)
2) Bad fuel pressure regulator. - Remove the vacuum line from it and see if it's full of gas. Attach a syringe for mighty-vac to the regulator vacuum line, it should hold vacuum

My guess is #2 since it wouldn't start a third time.
The kind of dirty that doesn't wash off :eyebrows:

Adrian Thompson
Posts: 170
Joined: Mon Mar 12, 2012 10:14 am
Number of Saabs currently owned: 1

Re: Project Loki - 1988 classic SAAB turbo

Postby Adrian Thompson » Sun Nov 16, 2014 3:14 pm

Good suggestions guys, I'll check as soon as I can. Right now I'm stuck at my daughters baby shower. Yes, I've never heard of guys going to a baby shower before, but I'm not the only one here and I'm under orders!! I'm also too damn young to be a grand parent.


Anyway, I'll check, but my concern is the oil coming out of the turbo flanges that can be seen in the pic of the turbo
Project Loki - 88 900C - future TSD, Rallycross and track day toy


Return to “Projects and Build Threads”

Who is online

Users browsing this forum: No registered users and 2 guests