Date: Mon, 21 Aug 2000 22:39:18 -0400 From: Four Weis <mweinopsamcom> Subject: Re: More cold-start questions (long)
You have many questions which the more technical Saab owners could answer in more detail. Get a good set of metric sockets and the appropriate tools before you start anything. It will make working on the Saab a pleasure instead of a series of frustrating problems. If you don't know already, you will find many uses for the 10mm and 13 mm sockets and wrenches on a 900. Life will be a lot easier with a set of Torx drivers. You will need a good multi-meter to help diagnosis you idle problem, which is probably due to multiple reasons in the fuel and ignition system. Good luck! "Scott I. Remick" wrote: > Having solved my occasional starter problem, I move onto hopefully easier > things on my stubborn 1984 SAAB 900S. Today, we talk about rough cold- > starts. I've got a lot of questions... any takers? > > First some background... > > After starting, even when it was run not too long ago, it will sometimes > run for a few seconds then die. We might go through this another couple > times, then she'll stay going... barely. The engine sounds awful, as it > seems like not all the cylinders are firing. Touch the gas at any point > and she'll threaten to stall (if she doesn't actually). It'll take a > little while of running like this in neutral before all cylinders catch > and it sounds normal. Yet even then, touch the gas, and the RPMs go DOWN > and it threatens to stall. You have to play this little game for a bit > longer still before RPMs go UP when you press the gas DOWN (novel > concept). > > And YET... even though you get to that point, trying it after the car is > in gear and expecting to go forward is interesting. It's as if actually > having the engine pull the car now makes it be troublesome all over > again.... the RPMs will drop when you touch the gas, it will threaten to > stall... release the gas, the RPMs go back up. Play this game for a > little bit, until it warms up further, then you start pulling the car > forward when you touch the gas. But the hesitation remains for a little > bit... you can put the gas down, and it's a moment before the RPMs > actually go up. And sometimes they'll go up a little bit, hang there for > a few seconds, then go up further, all without changing how far you > pushed down the gas. It's a while before all the power that should be > there finally appears. > > After a few minutes of driving, the car is PERFECTLY FINE and peppy. Go > figure. > > Now, it's due to have the plugs removed... I know this. I've normally > had it done elsewhere but she's an old car so I've gotten into doing more > work myself these days. Turned out the socket I had was the wrong size, > so I picked up the only metric one I could find (18mm)... hopefully it's > the right one. I'm going to grab some Bosch Platinum plugs (think it's > WR7DP?). Probably change the wires too. Distributor and rotor are brand > new. > > However, I'm looking at other stuff too. I'm concerned about the aux. > air valve. What's the proper way to test this component? I've got a > Haynes manual which is pretty useless on the subject. I took off the > hose opposite the electrical contacts and I can see the oval-shaped > viewport to what appears to be a metal disc inside. The part of the disc > exposed by the oval opening reveals two tiny holes... one centered, and > one partially exposed to the right so it could extend further around the > disc. On the several times I've taken the hose off to peek, it's always > at the same position. How does this part work (I know what it DOES, but > not how it operates)? How do I test it? Am I seeing what I should be > seeing? > > The Haynes manual describes an involved procedure of removing the fuel > pump relay, jumpering 2 of its terminals, and a few other things. When I > jumper the terminal the wire I use (14 gauge I think) gets EXTREMELY hot > so I stop that real fast and don't feel good about it. > > I'm going to try and check the cold start (fuel) valve too.. that seems > easy enough. Wondering about the air mass meter too... not sure I'm > looking at the right piece. Which is it? There's a box that the air > intake feeds into... it then splits off in 2 directions: one to the > exhaust manifold, and the other to the air filter. There's a wire from > this box that loops up into a probe in the air line right before it > reaches the throttle valve. There's another strange box that plugs into > the side of the same big rubber tube that goes from the air flow sensor > and curves around to the throttle valve... this box has some other > smaller air hoses going into it. I'm pretty sure that the AMM is one of > these two black boxes... but which? And how do I test? > > Should I look at the warm-up regulator? Just what does this do and how > does it work? > > Do aftermarket versions of these parts exist? (probably not) Or should I > go with new? Used? Rebuilt? From whom? > > Thanks for all your help! > > ----------------------- > Scott I. Remick scottnopsamuteralt.com > Network and Information (802)388-7545 ext. 236 > Systems Manager FAX:(802)388-3697 > Computer Alternatives, Inc. http://www.computeralt.com
 |
 |
 |
 |
 |
