[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: More symptoms of the poor running



if your vacuum (between throttle body and valves) just 'goes away' suddenly, i'm likely to think the issue is more of an air delivery issue. of course this only applies if the vacuum drop comes before the rpm drop. for this to happen, the vacuum loss would have to be unmetered, and LARGE (i.e. audible suction noise).

aside from this (and provided power loss comes before/during vacuum loss), it could be some sort of fuel issue that only happens on a cold start. a few causes come to mind:
- fpr sticking
- isv sticking (in this case sticking shut, but occasionally sticking and swinging open, causing your vacuum drop). test by removing the isv, checking for free motion. clean with carb cleaner and lubricate with a high grade oil. - dpr on its way out (not properly responding to the larger currents it sees on a cold start). test by watching dpr current - especially helpful if you can watch it while the problem is there. use an analog meter if possible, or at least a fluke with a fast updating bar graph.

hth
Al

----- Original Message ----- From: "Julie Macfarlane" <juliemac57@hotmail.com>
To: <scirocco-l@scirocco.org>
Sent: Thursday, January 13, 2005 9:47 PM
Subject: More symptoms of the poor running


Engine 2L 16v
Electrical: 88 16v harness
Fuel CISE

Engine starts well. One crank and operates.
Low rpm and rough idle. I had to open the air bypass screw a few turns to idle at 950-1K.

Problem. Power loss. Vac drops from 18" to 0 rapidly, almost stalling. Fluttering the pedal can keep the car running.

The idle feels "buzzy", a rough edge to the running. (poor desc I know)

Keeping the idle abve 1500 for a few secs will cause the rpm/vac to drop again.
Only fluttering the pedal will keep the engine running.

This will last for a minute or 2. The engine then will run correctly for the rest of the trip home.

I checked the plug wiring and replaced the fuel filter. It seems to be intermittent.

Any help appreciated!


Julie Macfarlane
"Its not just a car! Its an adventure!"
1981 MKI 2L 16v w 2Y
Amsterdam NY



_______________________________________________
Scirocco-l mailing list
Scirocco-l@scirocco.org
http://neubayern.net/mailman/listinfo/scirocco-l



_______________________________________________
Scirocco-l mailing list
Scirocco-l@scirocco.org
http://neubayern.net/mailman/listinfo/scirocco-l