Date registered: Dec 2014
Vehicle: 1991 560SEC
Location: Woodinville, WA
Mentioned: 3 Post(s)
Quoted: 164 Post(s)
Testing Cold Start Valves on a Gen1
So my 85 500SEC has a bit of lethargic start. Had some time today, and suspecting the Cold Start Valve wasn't firing, I did some tests.
Fuel pressure is good, injectors are all new, accumulator is new. After starting, car runs and idles flawlessly.
There fuel pressure in the line to the injector so fuel distributor is good.
I pulled the injector, put it in a jar and turned the ignition on - no fire.
Tried 3 different cold start injectors I've collected from parts cars - no fire on any.
Removed the wires from all the temp sensors thinking that could be a problem - no fire
I'm running a Gen2 FPR so I can get the pre-prime function, so I swapped out to my original Gen1 FPR - no fire.
Voltage test - none that I can see. even a blip.
Now I'm stumped. Nothing I've tested is triggering the Cold Start Injector to fire. Anything I'm doing wrong?
1991 560 SEC Euro
1986 420 SEL
1985 500 SEC (US)
1983 500 SEC (Euro)