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Discussion Starter · #1 ·
This car has been very problematic. First I got the ignition working and the car would run, but it was underpowered. I thought it was a fuel pressure problem. I remembered the fuel filter has not been replacedinthe 15 years of owning the car. I went to change the filter and I took out the fuel pump fuse while the car was running to get some gas out. I replaced the filter, but now there is no power to the fuel pump. This car has a history of bad wiring.

One more curious observation, once when the battery was low the car had significantly less power then I charged it up and it suddenly had more power but it still was slow. I think the source of the problem is wiring but I don't know where to start.

I know for a fact the ignition is working fine because when I spray a lot of starter fluid the car starts then dies.
 

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Always start with making sure your grounds are good. Always.

Then get a multimeter and start looking at connections to make sure they're getting power across 25 years of corrosion. But grounds first.

And for goodness sakes, when working with electrical never let the smoke out of the wires!
 

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Discussion Starter · #3 ·
Thanks for the quick reply. I don't know what else to test, in fear of frying a lot of fuses and other electronics. I know for a fact that the fuel pump is not getting powered and that the fuel pressure is low or not existent. What circuitry precedes the pump? I read the two components leading up to the fuel pump are ecu and relay, but I can't find them.
 

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Wiring...

I remember reading that 1985 C900's had wiring that deterioated by hardening and breaking insulation causing all kinds of problems. Some mid 80's Volvos and Ford Contours prior to 1998 had the same problem. The wiring on my 1997 Contour Sport hardened so that the insulation hardened and broke like a pencil exposing the wires. Fellow Saabers - correct me if I am wrong about 1985 wiring. I believe 1985 was the only year that used the hinky wiring. Your best bet may be to get a wiring harness from a '86 or '87 and replace your '85 wiring. If I am correct about the 1985 wiring, then your problems will continue to get worse. Sorry to be the bearer of this news.
 

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Discussion Starter · #5 ·
I think you are right, the wiring is absolute crap. I have the wiring charts, but I don't know where the fuel pump relay is.
 

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I think you are right, the wiring is absolute crap. I have the wiring charts, but I don't know where the fuel pump relay is.
fuel pump and starting relays are located above the ecu (fuel control) in the rt.hand footwell. You'll have to pull back the carpet to see them.

In the junkyard the other day and noticed a lot of the wiring on an '85 was broken everywhere...

Don't know how far you are from albuque but...
http://www.upullandpay.com/albuquerque/search-inventory
Also don't know your time vs. money budget. I'm assuming such things aren't available new but I could be wrong...
 

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Did you try the fuse-jumping thing to bypass the relay?
 

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Bobsverts is right on the money. I remember in the early/middle 80's Volvos and Saabs for a few years were being forward thinking-earth friendly and had this wiring insulation that was absolute carp after about 15 years of use. Good call Bob!
 

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I'm also told '89 was a cost-cutting year and it showed on the wiring?
 

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Discussion Starter · #11 ·
So I see where the wires go to the relays under the the steering wheel. I can't figure out how to take that pannel off. I see three screws I take them out, they are long, then the instrument pannel comes loose. So are the screws somewhere under the instrument pannel. I would like to try by-passing the relay, but first I have together it.
 

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So I see where the wires go to the relays under the the steering wheel. I can't figure out how to take that pannel off. I see three screws I take them out, they are long, then the instrument pannel comes loose. So are the screws somewhere under the instrument pannel. I would like to try by-passing the relay, but first I have together it.
For diagnostics I think you can more easily bypass the fuel relay at the fuse block under the hood. I'm guessing your '85 will be different than my '91 so I won't use #'s. Just find the fuse for the fuel relay and something always hot/on like your hazarad lights. Jumper them together, you should hear your fuel pump working. Try starting the car--if it starts than somethings wrong with your fuel or starter relay (or wiring) to you ecu.
 

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Discussion Starter · #13 ·
The by pass got the pump working,but the fuel system sounds like it is full of air. I just installed a new fuel filter so inlet it run, but there is still air or what sounds like air. I can hear the air and the fuel does not sound pressurized. The tank is half full. Should I leave the pump on for longer? The only thing is I left it on for about 2 min. It would seem like there is a leak but I don't see or smell gas. I know the ignition works because I kinda starts with starter fluid.
 

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You could try cracking one of the banjo bolts on the end of the fuel rail and then running the pump. You should get fuel coming out immediately... Be ready to close the fitting as soon as you do.
Have a rag in place to catch any spray.
*Be very careful of any sparks!*

Best to have a fire extinguisher handy and a helper for the "just in cases" we don't like to think about but always should...
 

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Discussion Starter · #15 ·
I'll have to try that tomorrow. Does the fuel pump only run when the engine is running or cranking? If it does could it be possible the wiring is fine and it's just the trapped air that's screwing things up?
 

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I have the same year 1985 car as you. I replaced alot of the loom and the ignition switch to sort out gremlins and certainly the insulation was completely munted! especially across the top of the inlet manifold . As it moves closer to the firewall and away from the heat insulation seems to improve .Id be very suprised if it wasnt some wires touching .While you are at it go under the dash and trace everything you can you will no doubt find a few problems and in the process get to know how each component of the electrical system a bit better.I removed a whole lot of defunct crap while I was at it ,. Cruise control entire AC system etc . I dont suggest you do that if you are into keeping it original !!.Once sorted hopefully you will have a great car that you can start to trust .
 

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if you get a spare battery direct feed the terminals and it will run no prob and will create the pressure required.
not sure what the top of pump looks like (model) but if it has the IN and OUT lines, are they the right way round
 

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The by pass got the pump working,but the fuel system sounds like it is full of air. I just installed a new fuel filter so inlet it run, but there is still air or what sounds like air. I can hear the air and the fuel does not sound pressurized. The tank is half full. Should I leave the pump on for longer? The only thing is I left it on for about 2 min. It would seem like there is a leak but I don't see or smell gas. I know the ignition works because I kinda starts with starter fluid.
Your fuel pump is a pusher pump so it's not sucking air unless it's sucking air at the tank. Should be fairly easy enough to tell...Do you see any fuel leaking out when you're jumping the pump to get it running? As Banman suggested, you can crack the banjo bolt fitting and see if it sprays a bit of fuel.
 

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Discussion Starter · #19 ·
So I opened the bolt and it sprayed when the fuel pump was on. Noise is coming from the pressure regulator. The ignition is fine. I can't figure it out!
 
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