Diagnose my 951: Runs rough, then great
07-23-2004, 12:23 AM
#1
Three Wheelin'
Thread Starter
Diagnose my 951: Runs rough, then great
My 951 is my daily driver until I put my new engine in the tercel. (Anyone want to buy a Saab 900?). She's been acting a bit weird on start up though, and it's got me concerned. I'm almost 100% certain it's a vaccum issue, but tell me what you think. All these symptoms appeared after putting in a new TPS.
- Starting the car cold gives a stumbling idle. At the bottom of the cycle, I can hear a 'pssssst' near the area of the idle stablizer. It revs up and drops again immediately. (Down to under 1000 RPMs, peaks at about 1300 RPMs).
- The A/F meter reads closer to the lean side of the scale, and doesn't clear when I take my foot off the gas. (Normally it reads right on the line between stoich and rich all the time when my foot is on the gas, and goes off when I'm off throttle). It reads towards the lean side of stoich (Yet, still very stoich indeed), and sits in the lean when my foot is off the gas.
- After the car is warmed up, it idles at a SOLID 1400 RPM. Dang it.. thats much too high. The adjuster screw doesn't help lower the idle. The car pulls hard and runs GREAT after warmed up. (IT still pulls when not warmed up, but I don't like to do that.)
Is it my ISV or TPS, or a vac tube?
If it's the TPS, how do I adjust it properly.. I followed the clarks garage guide and it clicks right off idle.
What's your diagnosis?
- Starting the car cold gives a stumbling idle. At the bottom of the cycle, I can hear a 'pssssst' near the area of the idle stablizer. It revs up and drops again immediately. (Down to under 1000 RPMs, peaks at about 1300 RPMs).
- The A/F meter reads closer to the lean side of the scale, and doesn't clear when I take my foot off the gas. (Normally it reads right on the line between stoich and rich all the time when my foot is on the gas, and goes off when I'm off throttle). It reads towards the lean side of stoich (Yet, still very stoich indeed), and sits in the lean when my foot is off the gas.
- After the car is warmed up, it idles at a SOLID 1400 RPM. Dang it.. thats much too high. The adjuster screw doesn't help lower the idle. The car pulls hard and runs GREAT after warmed up. (IT still pulls when not warmed up, but I don't like to do that.)
Is it my ISV or TPS, or a vac tube?
If it's the TPS, how do I adjust it properly.. I followed the clarks garage guide and it clicks right off idle.
What's your diagnosis?
07-23-2004, 03:48 AM
#2
Lazer Beam Shooter
Rennlist Member
Rennlist Member
Check those vacuum lines that are around the idle stabilizer. Mine was like that because it was cracked. It wasnt a problem until i messed with the idle stabilizer, then the hose crumbled by me looking at it. Eventually it broke into two and the car would barely stay on.
