RENIX wants valid signals from BOTH the CPS (Cranskhaft Position Sensor) and SYNC (camshaft position sensor) before it will fire the fuel injectors and the ignition - and it wants to see an estimated crankshaft speed of 300rpm. There are various reasons posited as to why - many apocryphal - but we learn to live with it.
RENIX will start without a valid SYNC signal (it will "guess" until it hits a runner, I've tried this,) but the condition is quite obvious. RENIX will NOT start without a valid CPS signal - and if your CPS is on the way out - or has a shonky connection - that could delay starts.
The engine will start right up with Tbody cleaner for much the same reason it will with ether - it's easier to light than gasoline vapour, and probably ignites upon compression. Once that gets started, and the ECU starts firing fuel injectors, it becomes self-sustaining.
Also, failing/corroded/dirty mains can cause slow crank (delaying starts,) and a dirty/corroded/failing ground strap from the cylinder head to the firewall WILL cause trouble (it's called a "RENIX Killer" for a reason!)
Also, a failing/dirty TPS (yours is probably getting old...) will cause trouble with starting. It usually won't prevent starting, but make starting more difficult and cause idling trouble.
Check, in no particular order:
CPS connection (3-pole Delphi Weatherpack with two wires in - you'll see this at the back of the fuel rail. And, a good sensor should show something like 125-275 ohms at ambient temperature.)
TPS action/adjustment (better to check with analogue ohmmeter, than digital. You're looking for a clean, smooth sweep of the needle when you move the throttle)
SYNC sensor (Use analogue voltmeter set to 15VAC. Backprobe with wiring still connected - + lead to BLU wire, - lead to GRY/tracer. Crank engine, you should see about 5VAC.)
Check for vacuum leaks (just for giggles - these can cause all kinds of Hell!) at the manifold mounting surface, throttle body base, and all Nylon engine management vacuum lines. Vacuum lines can be had from NAPA for RENIX - about $50/set, and all three part numbers you'll need are posted on here somewhere...)
Report back after testing, and if you need more detailed test instructions, we can help you.
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