Lean condition/head swap questions

[YungICY]

So I think I finally got to the root of my lean condition issue. Today I pulled the spark plugs out and one of them was missing a good chunk of it. I replaced it with a good plug and nothing changed. This leads me to believe I have a chewed up valve or even a hole in my piston. Assuming its my valve and that piston isn't getting compression and not firing, my logic tells me that the o2 sensor would read a lean condition. Would I be correct in assuming this?



Question 2) this motor is an 88 (with a roller cam). I also have an 85 2.3 waiting for a rebuild. The head is in good shape but the cam and followers are shot. Is it possible for me to swap the cam, followers and lifters from the 88 head onto the 85 head (keeping the good 85 valves) and install the 85 head onto the 88 block?









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[Kenneth S]

The roller cam, followers, and lifters can be swapped into the 85 (or really any 1994 to 1974 heads) with no modifications.

 

[RonD]

If just one cylinder was leaning out, then no, it probably wouldn't set a code and O2 sensor might report a slightly high O2 level(lean) and computer would run system richer but condition in that cylinder might still be too lean and cause it to overheat.
This type of lean condition almost always causes pinging sound before any damage occurs.

Could be that cylinders injector or a leak in the intake at that cylinder.

Or the whole system was running leaner because of O2 sensor fault and the one effected was just the first to show it.

 

[YungICY]

Thanks guys.



I'm not getting any codes thrown. I'm getting the lean information from a narrowband air fuel ratio gauge. My thought process is that I'm getting little to no compression in that cylinder. What leads me to believe this is that the motor doesn't run rough like it would with a bad misfire. And there was no way I was getting any spark with the plug that I pulled out this morning. My logic tells me that if the other three cylinders are operating as normal and the one is basically just acting as a small air pump if anything then there isn't as much exhaust gas in the exhaust as the should be and the exhaust gas that is missing is just being replaced with fresh air/unburned fuel thus showing too much o2 on the o2 sensor.



My mileage has went to shit since the issue started and I would imagine that it because of a loss of power (so I have my foot in it all the time) and also because the o2 sensor is getting a lean condition therefore dumping extra fuel in to compensate.


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