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hi everyone :) i recently bought a 2002 saab 9-3 and have been going through it fixing all the little issues it has. so far ive replaced the headlights, fixed the turn signal, given it an oil change, replaced the control arms (bushings were toast), fixed the rear wiper, fixed the license plate mount on the rear, and the other day for the first time i tried the cruise control. it would hold speed for a second... start accelerating... slow back down... and repeat. each cycle it would go a little bit faster. when it hit 90 i shut it off. i figured maybe throttle position sensor but i cant find a listing for one. also- when i was coming home from work and pushed in the clutch to slow down to park the rpms went up to 3k and back down without touching the accelerator. im thinking both issues are related. any ideas?
thanks :)
 

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I'm intrigued by your cruise phenomenon and will look forward to the solution, but I can advise that there is no TPS, its function being performed by the ECU and the electronic throttle.

Briefly, the throttle cable turns the black plastic cam, which doesn't turn the throttle plate. It turns a potentiometer, informing the ECU what is demanded. The ECU takes a look at various factors and signals the electric motor in the throttle unit (within the black plastic end cover) to operate the throttle plate and another potentiometer. The voltages of the to pots. are monitored to ensure that what is demanded is actually supplied.

If it goes into limp mode, the throttle cable IS directly connected to the throttle plate.
 

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I think you need a replacement throttle body or a rebuild. You can try one from the junkyard... but it may not be any good, so find a u-pull that takes returns.

But, before I replaced the TB, I would check all vacuum lines (especially the 4mm lines. They tend to get baked over time). 10' is enough for the whole car (8' will do it, but if you want a margin...). It's one of the first things we do after buying one of these cars. Slice lengthwise off fitting so as not ti break anything. Extra careful with the one that has the check valve in it running to the nipple on the cam cover. If you break it, a generic replacement is fine. That one should also be oil/gas resistant, the rest can be 4mm-5/32" rubber or silicone as you prefer.

If that doesn't do it, the EPC will let you figure out which TB's fit your car by first locating the one matches your year/model/engine, then by searching for that part number among all models/years. Because I'm overly curious, I searched and found that you can use a TB from a 9-3 2.0 or 2.3 from '99 to '02 & '03 convertible or a 9-5 2.3 from '99 to ' 03.

EPC & WIS download: WIS and EPC for Windows 10 - SaabCentral Forums
 

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The thing that makes the pedal work and the thing that makes the cruise work are the same thing... in broad terms if one works they both should. The pedal is a "torque requestor" and the cruise is a "speed requestor," and it's the same ECM that does the logic. I'd wonder if maybe the stalk switch is what's goofy, making erroneous speed requests. I'd wonder if Tech 2 can report on that.
 

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I'd also recommend checking the stalk. I can;t find it now but I had a troubleshooting guide for the ng900 that walked you through a test mode which tested the stalk functions and other parts. Not sure if it applies to the 93 (or at least the stalk functionality which seems really similar) but it couldn't hurt to try. Alternatively pick up a spare stalk on fleabay or at boneyard to eliminate it as a suspect.
 
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