I've had an ongoing problem with an '89 volvo 740 8 valve non turbo.
It starts and idles fine in cold weather but after it warms up.. intermittantly, it starts and bogs as if starved for fuel. I had some spare parts of another car. I tried replacing the ignition module, knock sensor,
AMM, and the ECU. I have checked the charging system for high ripple - is ok.
The o2 sensor is after market (1 year old) and there is a new Fuel pressure regulator. Plugs are new platinum (good colour) wires test good and no apparent problems with the distributor cap or rotor.

It appears more in warm weather. Also, when I reset the code in the computer it acts up badly , then begins to work fine. at the worst You can hold the accelerator to the floor and it will not exceed 3000 rpm ...back off and it idles fine.

Another problem ...I think is related is the fact it blips the throttle on deceleration at 1400 rpm Since the AMM and the temperature sensor are governing this... I am going to try a new temp sensor. I haven't been able to find much on what signal is sent top the EZK ignition computer or what it does with the signal. advance /retard likely