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Erik,
I have an '84 900S, (8-valve non-turbo, like yours). I'll tell you what I know, using your text as a base for my reply...
"One is on the outside of the bellows curve and has electricity connected to it" > This is the deceleration valve (it cuts off fuel to the cylinders when you let off the gas--decelerate). It receives an electrical signal above about 1575 RPM, if I remember correctly, and it is only found on manual transmission models, (1982-1988 8-valves). The 8V Bentley manual gives good info on troubleshooting this.
AND "the other is on the bottom with a very stiff cable coming off of it." > This is the thermo-sensing element for the air temperature control. The part that sits in the rubber bellows is the wax-filled thermostat. It is connected to a cable, and moves the cable depending on temperature. This cable runs down to the little 'flapper' box in front of the air filter housing, which mixes the ambient temperature air coming into the air filter with warmed air (taken in through the approx. 2.5" aluminum pipe coming from the area of the exhaust manifold). It is NOT exhaust which is mixed in with ambient air; rather, it is just heated air drawn from the heat shield which sits above the exhaust manifold. During cold temps (such as below 60 deg. F, I think), the flap is closed to ambient air (drawn from rigid plastic snorkel going to radiator) and fully open to the heated air pipe. Also, above about 80 deg. F, the heated air is closed off and ambient air only is drawn in.
The latter, is mounted in the air bellows with two plates and two screws which hold the sensing element onto the rubber with a sandwiching setup (a real technical term, ha ha). I guess it COULD get a bit loose over the years and create an air leak and throw off the VERY picky K-Jetronic system.
On the former, however, those decel valves aren't supposed to cause any driveablity problems. It apparently is an emissions control item.(Mine isn't working, my mechanic--a SAAB specialist--told me so. He said he didn't bother with replacing mine, but knowing I like to tinker with my SAAB, he said if I did replace my decel valve, I might see a 5-6% increase in gas mileage. He said other SAAB owners have had those same results.)
So, on the whole, I don't know if those two items are your acceleration problem. Does the bad behavior only occur when the engine is cold and/or not yet FULLY warm?
Post back with full symptoms. Hope this helps!
Micah in NC
'84 900S, 209K mi.
posted by 208.61.12...
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