Fw: cold start weirdness

Huw Powell audi at humanspeakers.com
Fri Jan 16 22:56:48 EST 2004

>>>Three of us have similar problem - temp no start when cold, or after 10
> min
>>>What do you think of the [CSV] switch idea?
>>Sounds like a waste of energy to me.  It is as much trouble
> **** I thought it might be some trouble to wire up. But, actually, its
> simpler than I thought. The cold start valve always has 12 volts on it - G/R
> wire. The ECU grounds the BR wire to fire the injector.
> All that is needed is a simpler 2 wire (off-on) pushbutton switch. Splice
> one switch contact to the BRN wire, and wire other switch contact to ground.
> Thats it.

Right, exactly.  That's *more* work than testing the thing in the first 
place!  Now, if there are other cold start issues involving "not enough 
fuel," a rig like that might get you to warm weather to fix it right. 
All I know, is if it this cold out, I don't want to be fiddling even 
that one wire through my firewall.  I want the car to start.  And the 
only time it has trouble is *dead* cold.  An hour and a half the other 
day at the supermarket, no trouble at all.

Since I don't commute (and leave my car all day at work), this only 
happens to me at home, so of course my attitude towards "fixes" is 

All I know is, that if I went out right now into the field with my 
battery booster, the 82 Coupe and 87.5 CGT's would fire right up with 
one crank.  Boo hoo...

> When stuck in a supermarket parking lot, freezing my nuts off, and with no
> tools or test equipment to play with . . that pushbutton switch idea dont
> sound too bad.
> This would just be a temporary measure to prove an assumption, and eliminate
> the ignition system.

Again, I say it is just as easy to test/fix the CSV system.  And if it 
doesn't help, it only proves it wasn't the CSV, it doesn't tell you what 
is *really* wrong.

>>Troubleshooting the CSV system is pretty simple, really, since there are
>>only one or two parts.
> **** Its not so simple when the problem occurs whenever it wants to, and
> goes away just as quickly. There are three of us now that have a similar
> problem. And no solution in sight.

The CSV is too simple to create lots of random problems.  It also does 
not do very much.  I think that the idea could be useful as a temporary 
diagnostic (not hard wired to pass. comp.), if your bad starts are 
predictable.  Me, I'm gonna test the thing as soon as it goes above 15 F 
out.  I'm gonna do a lot of things if it ever gets that warm out, like 
some gardening, tanning, paint the building...

> **** If it was an air leak, why doesnt it do it every time its cold?

On my car, it does.  And *only* then.  And as soon as it catches, at 
all, it runs fine.

> That
> simple pushbutton switch would quickly eliminate this possibility.
> When it dont start, hit the button. If it now starts, its lean. If it dont
> start, its ignition.

Still not actually diagnosing the problem though.  See what I am trying 
to say?  So it "fixes" it.  Now, what is wrong?  Air leaks?  Bad CSV 
control?  Fuel issues?

> Maybe we can get this thread as long lasting and convoluted as the
> torque/extension tool thread. Hey, we gotta do something on these cold
> nights.

It's good to have dreams... and live them to their fullest!

Huw Powell



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