I'm having the same issue as you, besides the fact that my transmission seems to shift perfectly fine. I recently changed the oil and didn't see any indication of a blown head gasket. Might try a compression test next. I'd also like to swap from TBI to carb within the future though, so replacing intake gaskets is a given and it should eliminate the IAC completely. Nice looking truck! Ever thought about starting a build thread for it's future?
I plan to drive it daily and keep it mostly stock. I like the unmolested look.
FWIW - You should keep the TBI. The TBI rebuild is $30 and takes an hour. You can get a lot of performance out of the TBI with very little cost. A performance chip is $100ish. Very cheap. The carb swap will work and give you performance but the same can be had from TBI. Just one man's opinion.
The previous owner gave me the intake gasket set. If I were buying the parts, I would have gone down to the heads, had them rebuilt, installed new lifters, etc. I'm fairly certain the valves are leaking and causing the compression drop. Instead of heads, I put the money into tires. Heads will happen in a few months. If I can find a decent set of TBI heads, i might buy them and get 'em rebuilt. That way, I can be in and out of the engine in a day.
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