How to find vacuum leaks

[Larry C Leung]

Exactly, as noted earlier, see www.sjmautotechnik.com for a complete
description (though Huw does it perfectly here!)

LL - NY



On Sat, 04 Aug 2001 18:29:00 -0400 Huw Powell <audi at mediaone.net> writes:
> 
> > Correct me if I'm wrong but isn't the stalling directly related to 
> the
> > removal of the oil cap or dipstick? In other words, isn't THAT 
> your vacuum
> > leak?
> 
> Rob is correct, you have it backwards.  engine runs fine capped, 
> stalls
> when uncapped, tends to indicate *no* vacuum leak.
> 
> If it didn't stall (and this is trueer of turbo's than NA, btw), 
> then
> its already been adjusted to compensate for excess air and the
> cap/dipstick test *does not* stall it since its not enough extra
> unmetered air to lean it out to the point of stalling...
> 
> > > Finally got my coolant expansion bottle, installed it and while 
> waiting
> > > for the cooling fan to come on during the bleeding, I decided to 
> do the
> > > dipstick test to see if some of the stumbling and hard starts 
> might be
> > > vacuum related. Well, pull the dipstick, it stutters, loosen the 
> oil cap,
> > > stutters worse, lift the cap, it finally stalls. Soooo, I have a 
> vacuum
> > > leak. The problem, I can't tell where. The hoses I checked so 
> far look
> > > good, I know I do need a valve cover gasket, but I can't tell if 
> it's
> > > something else (it seems from the dipstick test that the leak is 
> likely
> > > more severe than a mildly seeping valve cover gasket!). I recall 
> someone
> > > on the list saying something about propane, but I'm not so sure 
> what they
> > > said...
> 
> -- 
> Huw Powell
> 
> http://www.humanspeakers.com/audi/
> 
> http://www.humanthoughts.org/
>