In warm weather or whenever the engine is already warm - it starts right
away and runs excellent. In cold weather (below about 40 degrees F) it is
hard to start. After about 6 trys it will start. What is the most probably
cause - cold start valve, aux air regulator, thermo-time switch or what?
What is trouble shooting sequence. I would like to start with the most
probable cause. I once had a Datsun 280ZX with a similar problem. I hot
wired the cold start valve to the battery (with inline fuse) with a spring
loaded off button on the dash. During a cold start I would just hold the
button in for a few seconds while cranking and it would immediately start.
That worked for a few years until I sold the car. Would the same procedure
work OK in this Rabbit? Thanks Gene

On Fri, 12 Jan 2007 08:48:01 -0500, "Gene" <klein15 (AT) cox (DOT) net> wrote:


a flashlight will pass through .
cold start injector : when COLD pull the injector and place it in a
glass jar ( with the fuel line and
wires still connected). Pull the connector off
the thermo-time switch and jumper across the plug terminals. When the
starter is cranked a cone shaped spray of fuel should be seen.

thermo-time switch : removed the plug from the cold start valve and
.. bridge the contacts with a test
light or voltmeter , pull the coil from the center of the distributor
and ground it with a jumper wire. Again this needs to be done when
it's below 32 COLD . engauge the starter and the test light
should light , or the voltmeter should indicate voltage for three to
ten seconds depending on how cold everything is.

I vote cold start system if your red lights stay on in the instrument
cluster while cranking.

Does it have power after it starts when cold?
I have seen 2 VWs lately with just this problem. One had a terminal
slightly pulled away from the cold start injector. The other had a bad
starter that would not supply power to the cold start system.

later,
dave
(One out of many daves)


"Gene" <klein15 (AT) cox (DOT) net> wrote

Thanks to Sam & Dave for their input. I pulled the electrical connector
from the cold start valve, put a volt meter across the contacts. No voltage
while cranking!! Apparently the cold start valve is not working because it's
getting no "juice." So - no what, what do I check next?? Thanks Gene

"Gene" <klein15 (AT) cox (DOT) net> wrote

But did you jumper the thermo-time switch connector? You have to make
the computer think the engine is cold.

Also, the thermo-time switch doesn't stay closed forever; at 20C (68F)
it only stays closed for 1 to 3.7 seconds. Once it opens again you
won't see any voltage at the cold start valve.

Here's the thermo-time switch test:
1. Make sure coolant temperature is below 86F. Let it sit all night.
2. Disconnect the coil wire from the center tower of the distributor
cap and connect it to ground, using a jumper wire. This prevents the
car from actually starting.
3. Disconnect the cold-start valve harness connector and connect a test
light across the connector terminals. Not the switch; the connector
that has wires connected to it.
4. Actuate the starter and watch the test light. It should light for a
few seconds. If this doesn't happen you didn't follow steps 1-3, or
the wiring is bad, or your computer is broken.

Mike

Yeah do what Mike said and disable the ign.
I would check the wiring at the cold start valve with a KNOWN working test
light (or voltmeter) to check that you get power to one of the terminals at
the cold start valve while your helper engages the starter. One will be
power only while cranking and the other will/should be grounded when the
thermo-time switch is functioning and the wiring and computer are fine.

A few things to check!
1. Check for power at the cold start valve terminals while cranking.
2. Also check for ground at the other cold start valve terminal.
3. You can also check the thermo-time switch and it's wiring at the switch.

<upand_at_them (AT) yahoo (DOT) com> wrote

On Sat, 13 Jan 2007 05:42:50 GMT, "dave AKA vwdoc1"
<vwdoc1 (AT) hotmail (DOT) com> wrote:

would be it's the starter causing the poor 'cold start' condition?
If so , i'm going to remember that troubleshooting aid.

Not quite, I am saying that the ign switch is bad and power is shut off to
the ignition while cranking evidenced by the red lights disappearing. ;-)
Sometimes you can move the key around while cranking and get those red
lights back on to start the engine.

later,
dave
(One out of many daves)

<samstone (AT) aol (DOT) com> wrote

Have you checked or replaced the Infamous CPR ? Control presssure
regulater if its bad your car will run good at one extreme either cold or
hot , what it does it acts like a choke it richens the overall fuel delivery
for a few minutes then leans out as it warms up yours may be stuck on
lean they are not fixable only replacabe there is a few tests you can do
but it involves pressure gauges etc the best thing since they are
expensive 60 USD plus is to get one from a wrecking yard. I have 3
spares and other must have cis goodies for my 82 2 dr jetta sunroof
..... let me know what worked
"dave AKA vwdoc1" <vwdoc1 (AT) hotmail (DOT) com> wrote

Thanks to all that responded. I believe the problem was in the CPR,
thermo-time switch or aux air regulator. These items are very expensive
new -- and there aren't many Rabbits in junk yards any more. To solve the
problem I hot wired the cold start valve to the battery (inline fuse) with a
spring loaded to off button (like a door bell button) on the dash. During
a cold start I hold the button in for 2 seconds maximum while cranking and
it immediately starts. Problem solved. Gene

"Gene" <klein15 (AT) cox (DOT) net> wrote