200 cold start problems

John Larson westcoast at mypowerpipe.com
Sat Jul 15 20:35:34 EDT 2006

so far i have checked

Injector leaks - OK
Sys pressure 5.8 bar
cold control pressure - 3.2 bar although it wasn't
stone cold, but i 
dont think it's a CP issue so wasn't too careful there
resid pressure 3.4 bar afer 30 mins
check valve pressure 3.2 bar after 30 mins
i cracked open the cold start valve, and WUR
connectors after the car 
had sat for an hour or so, i got a spray so there's
pressure there.
cold start valve is getting 12v whilst cranking
the 2 black coolant temp sensors are giving the same
reading, although 
for the price i will change these v soon.
I lifted the flow plate with the pump on and the
injectors spray nicely 
(they are spanking so i guess that's normal) and shut
off without dribbling.

haven't checked the CSV flow rate, yet, but te car
starts ok when cold, 
but has already started the same day
I am about to test the WUR resistance, but am pretty
sure that it will 
be ok.

as i say, I guess that it's fuel pressure, but the
tests seem ok
I'm thinking
1 accumulator
2. pump check valve
3. temp switches (but not convinced)
4. stuck CSV, but the economy seems reasonable. I'll
pull it off in 
about 10 minutes

anyone got any better ideas?"

Have you checked the mixture after it's warmed up?  New injectors nearly always require moderate to substantial adjustment of the mixture screw inside the airflow meter. This can be done by monitoring the voltage at the O2 sensor while it is unplugged.  The voltage should be around .5v.  With the wire attached, it should rapidly fluctuate from around .2 to .8v or so. Is this a CIS-E car?  Have you checked the infamous "spare" fuse in the side of the fusebox?  It's NOT a spare.  I can't even recall how many of those I've found missing over the years.  The cold start valve should ONLY activate at temps below 30-40 degrees F, and then only for 5-10 seconds, and only while the starter is engaged.  John


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