Volvo CFI system

[xxalexx at ix.netcom.com]

> Date:          Thu, 17 Sep 1998 09:38:54 -0600
> To:            diy_efi at efi332.eng.ohio-state.edu
> From:          Steve Jernigan <jernigan at chester.uccs.edu>
> Subject:       Volvo CFI system
> Reply-to:      diy_efi at efi332.eng.ohio-state.edu

> Hi Group !
> 	Hope someone can help. This is not really an EFI question, the old Volvo
> 240 (1977) uses a continuous mechanical fuel injection (CFI) system, but
> this one has an O2 sensor and what the manual calls a "frequency valve"
> which apparently adjusts the mixture in response to the sensor. After
> 260,000 trouble free miles, the ol' tank no longer passes emissions for

Check your O2 sensor output by splicing into line with a digital 
voltmeter. With engine hot it should be cycling.
If it is then with 260,000 miles most likely your CAT is gone.
Is there any smoke coming from exhaust?
The 1977 standards should be fairly high, to pass with no CAT.
Get a long 3mm allen wrench and stick it in a deep hole on your
fuel distributor press down and turn clockwise to lean mixture to
just the point before misfire.
Note disconnecting the lambda valve will most likely lean mixture. 
except for non-grey  MB.
alex