langer1 said:
The real reason is the Renix has no memory so it takes a couple of turns just to reset the timing and fuel mixture.
Thats also is why there's no check engine codes saved.
Half marks. Not only does the RENIX system not "store" or "throw" codes (it's pre-OBD,) but there's also the fact that the ECU has to receive a valid crankshaft position sensor signal (always,) and it wants a valid SYNC sensor signal (which it can work without,) before it will send triggers to the ignition and fuel injection.
I'm wanting to recall that it wants to read 300RPM at the crank sensor as well, but that may be apocrypha - I'm not sure where I picked that up.
The system can work without a valid SYNC signal - it will "guess" until it hits #1TDC compression/fire, and go forward from there. However, it will take a noticeably much longer time starting (don't believe me - disconnect the 3-wire terminal coming from the distributor and try it!) and you will know
something is wrong.
I've noted that keeping the battery charged up and staying on top of the starter helps somewhat. I've also got reports from the field that replacing battery cables (which are probably old anyhow, and not as well-sealed or as large as they really should be) also helps - this from people who have bought the cables I make. I don't think of that as apocrypha - I've noticed a slight decrease in start/crank times and somewhat faster cranking when I changed my own cables a few years ago - and I haven't lost either advantage yet (but I'm cranky, and tend to overbuild things.) Replacing/upgrading the cables will allow the start motor to draw full requested current, and that allows it to generate more torque, and therefore crank the engine faster (and get up to speed faster.)
I'm still inclined to try the check valve - I've just got to find one I can work with. Max FI pressure for the 4.0 is 39psi, so it's not that high (but higher than the 4-7psi used in carburettor systems, so it's still something to think about.) I haven't tried it yet - but I will give a report from the field when I finally do. Just don't hold your breath - most people do not look well with hypoxia...
5-90