I own a 87' Porsche 924S and I'm having a little trouble with it. I originally bought the car five years ago and restored it back to life. I have been driving the car for Two years now and have not any trouble with it until now. It kind of hard to explain what it's doing but I will give it a shot. When the car is running and the engine is cold the car runs really bad in the low RPMs. When you give it some gas it bog's down all the way through about 3,500 RPMs and then kind of breaks through and runs good in the High RPMs. Also when it is idling it wants to stall but it doesn't. I just bought New Spark Plugs, Wires, Distributer Cap, Rotor, Coil Pack, fuel filter, I also Bought some air flow meter cleaner and cleaned that. And the car is still running crappy. I anybody has got any suggestions I'm totally open for help.
Thanks,
Sergio

 

Two possibilities are the TPS and the idle stabilizer valve. I would lean more towards the tps, and the ISV does not affect the car at higher rpms. You can unplug the tps and you should be able to drive around. If the problem goes away, you know you found the problem.

Also, I would pull the afm plug, and spray the contacts clean.

 

How do you remove the TPS. I have the throttle valve off and I have removed the two screws from the TPS and I do not want to break it. Is there some sort of trick to getting it off or do you just pry it off? Also once you put the new one on does it have to be set specific way? Last thing what sort of cleaner should I use to clean my throttle valve?
Thanks,
Sergio

 

Please explain this topic in detail as I am the person who is not aware of any technical detail of automobile through this way I can get a brief idea of this technicality. Thanks in advance