[Author Prev][Author Next][Thread Prev][Thread Next][Author Index][Thread Index]

Re: Vacuum Leak Detection

Dave Conner <conner@cfm.ohio-state.edu> wrote:

I believe my "new" 91 200q has vacuum leak troubles.  So I tried
propane trick and got nowhere.  
The engine will run with the oil filler cap removed so I even
directed the propane into the oil filler hole and the engine rpm
did not change.
Your '91 employs the hot-wire Motronic injection, it_will_run
even if vaccum is leaking, unlike the earlier cars with
mechanical CIS injection.

I spent ten minutes directing propane at every suspect hose with
no vacuum leak detected.
When you come over to Philly next week I'll show you the "Vacuum
Leak Detector" by Lubro Moly. Contrary to Propane, this
stuff_stumbles_the engine if introduced into the intake tract.
Although it is still useless on your '91. 

[...] or do I just need to inspect/replace every suspect item one
by one?
I am afraid yes.

Igor Kessel
'89 200TQ -- 18psi (TAP)
'98 A4TQ -- nothing to declare
Philadelphia, PA