FI always too rich

[Alan Brase]

My 91 Vanagon 2.1 has developed a problem recently- too rich all the time. It is stinky at idle and will barely run when first started. Gets lousy fuel mileage.
Problem is, I can only get it into my garage for short periods of time.
I'm suspecting a sensor is out of whack, or bad grounds, but I need to have a good work plan so I can get it back on the road soon.
Any ideas on what ails it?
Thanks, Al
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Al Brase
Projects: 67 sunroof bug, 67 Porsche 912 Targa, 70 Westy
Dec 1955 Single Cab pickup WANT 15" BUS RIMS dated 8/55, thru 12/55
To New owners: 1969 doublecab, 1971 Dormobile
Vanagons:
80 P27 Westy JUL 1979, 3rd oldest known US
83 1.6TD Vanagon, 87 Wolfie Westy daily driver, swap meet home

[Ahwahnee]

One common cause of that is a short in the O2 sensor lead.

On mine one strand of the coax layer on that shielded wire got in contact with the spade connector on the inner wire of the green lead. That was enough to short out the sensor and make the ECU want to run rich all the time (well after the first couple of minutes as it ignores the O2 signal at first).

The check is simple -- disconnect the lead that comes from the O@ sensor (engine bay, left side, possibly thick green wire) and use an ohmmeter to see if the connector is shorted to ground.

All I did to fix mine was strip the coax back a fraction of an inch and fit some shrink tube over it to keep it well-behaved.

Could be other stuff too, but there's a place to start.

[Alan Brase]

[flopper]

First sensor that affects all the time is the temp sensor. Check it at various temps to see if in spec and check the harness. Some have said their ran rich with it disconnected mine would die at idle and not restart.
Maybe an injector stuck open can check if the fuel pressure drops to zero real quick after the key is shut off.
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85 Vanagon GL 7pass manual in the process of finding out all that's wrong.
One VW at a time so far, past memories...
75 Westy weekender, 92 Eurovan GL and to start it off 82 Vanagon GL 9pass.

[mattcfish]

Been chasing this issue for years on my 85 Digijet with a 2.2L upgrade. Hope you find an answer, I've tried everything.... I mean everything. Real rich idle, plugs look fine. Runs great otherwise.
Check TPS, check Cold start valve, and exhaust leaks. Look for any vacuum leaks using a propane can (not lit).
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71 Bay Window
75 BMW 2002
76 BMW R90S
85 Vanagon with 2.2L upgrade

[morymob]