Will not stay running when cold
#1
Will not stay running when cold
So.. I have a 1987 944s and when I start it when its cold, it runs very rough and will not stay running until it has warmed up. I have done new fuel filter, had pros clean the injectors, new pressure regulator, new fuel dampener, new plugs, wires, rotor, coil, cap.. What could be causing this?
#2
Burning Brakes
Could just be that the idle is a bit too low and the engine would tolerate it when the weather was warmer. Another possibility is the DME temp sensor going bad.
#4
Got Nothin'
Rennlist Member
Rennlist Member
One more sensor to think about. Engine Temp sensor. All of my cold start/cold running problems have been associated with this one. Latest issue I had was not the sensor itself, but rather the wiring to the plug. I pulled the boot on the plug back and saw the leads were shorting out. Separated them and the problems (rough start/stalling when cold) all went away.
#5
Rennlist Member
Check the engine temp sensor (as Pete suggests), and check for vacuum leaks. The latter can often close up as the engine warms, creating a situation only when cold.
#6
Intermediate
+1 on the DME Temp Sensor. It's an inexpensive part (<$20) and was able to replaced mine a few weeks ago and made a world of difference for my 86 951. I pulled the intake, replaced the gauge temp. sensor, and intake manifold gaskets at the same time. Also managed to inspect vacuum hoses.