Hello all,

My 91 240 with 215xxx on it gave me four check engine codes yesterday -

1-2-1
2-2-1
1-1-3
2-3-1

Upon inspection, my dad (who is stressed enough from repairs on his recently acquired 240,) noted a knock that seems to be coming from the valves. He did not find any other obvious issues that could be the cause of codes like this, including injectors, the 02 sensor, etc.

He believes it could be a fallen valve lifter, or bad valve lifters. I am struggling to find much information on this. Due to the amount of tear down to get to this particular problem to run a true diagnostic, I am trying to find some information before I take it to a shop.

Normally, my dad does the repairs on all of our Volvo's, however his 240 is occupying all time and garage space, unless we can figure out what the problem is hastily so the repair can be done in the driveway in one day. He has never seen it personally, and asked me to consult all of you wisemen whom he trusts (much more than a garage!)

Symptoms:
-Rough idle, especially after warm-up.
-Extremely rich fuel usage - appx. 8mpg
-Loud knocking noise, particularly when warmed up

If any of these codes or symptoms are something you have experienced, your insight would be greatly appreciated.