[Ian21401]

I also have a 1992 940, B200F, NA which I bought in 2005.
Have you interrogated the OBD fault code reader?
During it’s first year with me it developed a similar fault. The OBD fault code reader, position 2 (fuel) indicated Fault code 1:2:1 (MAF sensor signal faulty). I didn’t know much about that engine at that time and was advised to change the Lambda sensor, which I did ( a genuine Bosch one) and the problem disappeared.
A couple of years later a similar problem arose eventually causing a complete “fail to run” on my way home from work necessitating a recovery to my home. The OBD again showed 1:2:1. I bit the bullet and ordered a new MAF sensor from my dealer. £250.00 after discount). This cured the problem.