Struggling to understand a running problem and am looking at all suspects.

I see a "AC Relay" in LH-Jetronic 2.2 wiring diagram.
I tracked this from references to a "radio suppression relay" related to fuel injection that was noted as problematic and worth having a spare of.

This relay is located behind the AC thermostat switch in the center console.

I also find this "AC Relay" called a "Solenoid Relay" in the AC wiring diagram. This relay has leads that go to the Jetronic system "Fuel ECU".

The original "Radio Suppression Relay" is described as controlling injector firing to avoid interference with radio operation.

In my ancient memory I recall that when I had AC, and turned it on, the engine would pick up speed. That made sense as it was under added load to turn the compressor.

It strikes me as possible that the Fuel ECU is getting a false message to increase the fuel/air mix because it could think the AC is on.

So ... the questions are:

Has anyone found this relay to cause rich running conditions?
Is this relay like the Fuel Relay that has failing solder joints?
Are there any tests to check circuit integrity of this relay?

Please do not go to FPR, AMM, Temp Sensor, fuel pumps. O2 sensor, TPS, IAC ... and other issues
Thanks

'88 244 DL
B230F
LH-Jetronic 2.2

Hi Thomas,

Has anyone found this relay to cause rich running conditions?

No one has.

Is this relay like the Fuel Relay that has failing solder joints?

Sure. All the relays with circuit boards are prone to solder failures.

Are there any tests to check circuit integrity of this relay?

When turned on, the AC operates 10 seconds after motor started and continues to operate until temperature reached or turned off.

LH2.2 fuel computer does get a cue from the AC, but it isn't dependent on the relay. Its connection to the relay is at an input, but the microswitch on the back of the thermostat is the source of that signal. That switch is prone to failure, but I doubt it would contribute to a driveability problem. Easy to test: Pull fuse 12 and drive like that. Careful, if it rains, your windows may not roll up if they are powered.

Hope this helps!
--
Art Benstein near Baltimore

What do you call a fish with no eyes? A fsh.