90' 22re manual with 347,000km.

Just got this truck recently and I noticed that 4 bolts are missing on the valve cover. How likely is it that they just rattled out? Should I go ahead and put in a new valve cover gasket? So far the truck runs fine. Only codes I'm getting are 25 and 26 which so far I've isolated as a faulty O2 sensor. Unfortunately I sheared the stud off but I managed to get that section of exhaust out so hopefully tapping new holes will go smoothly.

Also how on earth do I take out the PCV valve?? I was pulling so hard I nearly lifted the front end off the ground

Here are some pics for reference:

Missing bolts on either side of the oil fill cap. Missing two others. Could it maybe be for an engine cover that has gone MIA?


Closeup of gasket

 

Not all of the holes need bolts. The only thing that holds the valve cover on is the four acorn nuts that have the thick rubber washer under them (Its the nuts just behind the holes you mentioned).

The bolt holes that are empty are for different configurations and different models. Some will be used to bolt down various brackets and others will not.

As for the PCV valve, I ended up taking out the grommet with it when I put a new valve cover gasket on my truck. The grommet is probably rock hard making the PCV valve hard to remove. Try to remove the grommet with the valve and replace that too.

 

Well that's a relief! Hopefully the PCV valve will come out next time.

 

Instead of trying to fix that heat cycled O2 Sensor Bung just get it new one so much faster.

After trying the first time and breaking a tap and getting it stuck I just cut the old ones off and weld a new one on .

In the great Northeast fighting with broken rusted hardware is a fact of life.

 

Already have a new sensor waiting to go in. I'll try to tap it first and see what happens. If it doesn't work, I don't have a welder but I'll see if I can clamp in on tight with something instead lol