CIS question
 

I posted before that I have an 82 SC track only car that was recently dyno'd running lean with an AFR of 14+ at WOT. I've identified that the dome lights and everything else on that circuit are not working. My question is does that mean the Lambda unit isn't getting power as well? If that is the case, would the fact that the frequency valve is not working cause it to run lean at WOT?

The fuse for the dome light powers the relay for the Lambda brain under the pass. seat.
No fuse, no power. Replace fuse and wiring.
Check this: With engine running, pull the relay off the brain.
Notice engine running worse?
Use dielectric grease on the pins.
Also, you can reach behind and feel the Frequency Valve vibrating if it has power.

Thanks Gunter. So if the frequency valve insn't working, will it run lean at WOT?

where is the dome light fuse located?

#18

If you are running Bosch K-Jetronic CIS with Lambda, the mixture is off without the Frequency Valve in all RPM's.

Did you replace the fuse? Did you pull the relay for the Lambda as described above? Notice a difference in idle? Do that first and let us know what you find.
(The Lambda brain is neglected and gets rusty, clean the pins and use dielectric grease)

Confirm that the FV is working, then I'll suggest what to do next.

You do not want to run lean in WOT. :(

I'll try this tomorrow. I've tried replacing the fuse before with no luck - it's not the fuse. I think i have an open circuit that I need to track down.