push starting a C900?

Nope.

I don't know of a thing that would explain that behavior.

Not terribly familiar with '87, but if there is a fuel injection ECM or computer-controlled spark, you will have no joy with a completely dead battery. The computer will not even know the engine is turning, no fuel pump, etc. Coasting a few feet at 10 mph will not generate enough juice through the alternator to get everything going.

the start process is not limited to truning the engine over, which is all jump starting it like this will do.

you also need battery power to run the ecm and other electronic systems.

this is true with SAAB and with other cars. my 92 olds is useless with a dead battery.

I don't know about the C900, but my 9-3 seems to have a very short first gear. I can well imagine the wheels slipping if I tried bump-starting it in first. Second should be okay, or even third if you have a decent hill.

Cheers,

Colin

As others have said, you need a little bit of juice in the battery to power the electronics. But I don't think that was your problem in this case.

You say "the front wheels jus screetched" - the simple answer is that you were using too low a gear - when roll-starting, 3rd gear is best bet.

It helps to not have an auto transmission as well. My C900's have autos so if I had to start them with a dead battery, assuming there isn't something else wrong electrical, I can't push-start the cars! Unless it's down a very long steep hill but I bet the torque converter would self-destruct with so much reverse power being applied to it. 8-)

Craig.

Your lucky it still runs after 18 yrs . good luck papa

Why? I see dozens of Saabs that old and older running around here.

My two running C900's are 22 and 20 years old respectively. Quite a number of SCCA members have Saab 99's in conditions right up to showroom pristine level (including their operating status).

Craig.

My 20 year old 900 T16 would start first time on the button everyday. If left more than two days, it would drain the battery if the alarm was set. But other than that, either started everyday, or with the alarm ground disconnected if storing a garage for more time while I was away. No worries, fired up every time. The problem was the 20 year old Saab turbo battery. Hard to find locally without taking a mortgage.

Is there something unusual about the battery? I've always just gone to Costco and gotten something close, never had a Saab Turbo though.

It's smaller than the normal 900 battery. At costco it say on the Bosch book Saab 900 (Not Turbo) Local shop looked up the model listed and it said "Dealer supply only" Didn't have the car with me, because the battery was flat so he couldn't measure up. But it didn't even list a part number, just the needed rating.

Yes, the battery must have some 'juice' in order to run the fuel pump. I left my running lights on one day and the batery was completly discharged. I tried roll starting the car to no avail. When I got a jump start, it started (jumper cables connected) after giving it a few minutes to charge my battery. Upon disconnecting the jumper cables, the engine immediately quit. I had to leave the jumper cables connected for about 5-10 minutes in order to have enough power in the battery. I also had one of those 'weak' regulators in the alternator that produced only about 13.5 volts. This is sometimes a problem with the bosch alterators. Worn brushes will also cause low power even though the 'idiot' light does not come on. Fortunetly you can buy new brushes (and complete regulator kits) that can be installed without removing the alternator.

Jim '87 C900 247K miles

forgot about the whole fuel pump thing. the last time i ever had to worry about my fuel pump, it was a mechanical one. since i never repaired an electronic one, i never thought about them being electronic.

here's a question though: even with the fuel pump off, shouldn't the fuel line be pressurized so that there would be enough to run the injectors a little until the engine kicked over?

mike

If you have enough voltage for the fuel injection computer to work, and for the relay that energizes the FI computer, and the electronic ignition (hall effect sensor and related electronics). A K-jet (mechanical fuel injection with electronic pump) push starts almost embarrassingly easy on a very drained battery, an L, LH-jet or Trionic (electronic injection) no so easily.

Bill

The fuel injectors are also electrically operated. Without power, they won't open. Additionally, if the ECU has no power the engine will -never- start. The fuel line won't hold full pressure for more than a few hours or a day at most.