Date: Fri, 23 Aug 2002 16:50:15 -0400 From: KeithG <noonenopsamspring.com> Subject: Re: cold start problem.
The 380 ohm value is a start point only. The procedure is on the web page: http://188.8.131.52/tuneup_folder/amm.htm more FI information is here. http://saabnet.com/tsn/faq/lhoverview.html KeithG bob stevens wrote: > Hi, > I know this might be a common topic, but I'm really > stumped by my 1986 900S. It has a cold start problem, > - only the first start of the day, after that it's > fine. > > The first attempt will bring the RPMS up to a high > idle, which will then drop over a few seconds, then > stall. The next attempts to start may then fluctuate > between high idle and almost stalling a few times, > before finally stalling. A few more start attempts, or > if I press on the accelerator a bit until it's > settled, and it's ok. The car will start no problem > for the rest of the day. > > I have checked and replaced the vacuum lines and > several of the manifold grommets, and a vacuum gauge > reads between 15-17. > > I sprayed carb-cleaner into the throttle valve, to be > sure there wasn't any gunk that could affect idle > speed, but it looked clean. The throttle position > sensor also works correctly. > > I also removed and cleaned the AIC valve, tested the > resistance across the three terminals (LH 2.2) and it > seems to match up to the Bentley specs. If I start the > engine cold with the AIC valve detached from it's > electrical connector the engine starts and levels off > around 2500 RPMS! I have no idea what this means, if > anything. > > Then I measured the resistance of the AirMass meter > and adjusted it to 380 ohms according to value I found > in the service manual. How far off from this value > would still be reasonable for a 1986 engine? And if I > need to adjust this setting, how do I find the "sweet > spot"? > > I even replaced the coolant temperature sensor with a > brand new one. > > Does anyone have suggestions? Maybe fuel pressure > regulator or pump? The car doesn't seem to have lost > any power, in fact it runs rather well. > Can I rule out the Oxygen sensor, because > the engine is cold? > Thanks, > Bob