So after the last run, there were several issues that I simply need to get addressed. one was a persistent fuel smell, another the exhaust leak, the 02 sensor (again) is acting up, and I've always thought this thing gets terrible mileage for the set up...
I've not been a fan of the Holley replacement TBI, but it was what I had and my hope of a replacement either being found (I have one, somewhere) or found at a swap meet just wasn't happening so today I went to the wrecking yard, spent $40 on these
the issue with the holley (the biggest issue) is the way they hold the injectors in place. GM used a bunch of screws to hold them down, the Holley just uses the air cleaner hold down.... to say it's inadequate is an understatement. It's worse thing is it doesn't stay sealed - it will do a nice spray pattern for a bit, but it will dribble and drip.
I cleaned up the TBIs, picked what looked like the best (it's the newest) and slapped it on
and I think the IAC is sticking, but it runs again (more messing with tomorrow)
which brought me to an issue or two I didn't realize
the is the old base gasket.... I think it's been leaking
back side doesn't look bad but see how close the witness mark is to the hold-down bolt? one of the bolts has crud from where it's been leaking up the bolt.... vacuum leaks galore
which I was all ready to take the blame for until I saw this
Holley uses a larger butterfly, it's been hitting but what's worse is that would create a tortured path for air and fuel to flow into the motor..... and of course, vacuum leak, uncontrolled fuel entry and I am hoping that I've found the source of what's killing my O2 sensors.... we will see, first step is reconfigure the throttle cable the replace the IAC....