Engine quit (Page 3/5)
Dukesterpro FEB 15, 01:12 PM
Dumb question, have you tried and alternate battery? I had this happen on my jeep once, where the battery would be fine until real load was placed on it, then it would shut off.
zkhennings FEB 15, 01:32 PM
They sell cartridges for label makers that have heat shrink tubing that you can print on. This is great for labelling a harness with. My Microsquirt I am installing in my 3900 swap has wires that are all labelled with their functions printed on them. I would like to do the same with the factory wiring I retain to make it super easy to locate things without having to trace wires to the C500, C300, or ECU connectors. Especially once they pass through the bullkead it becomes very hard to make sure you are tracing the correct wire.

I don't think it would be hard to produce a generic harness where pins that are unneeded can be depopulated, but the limiting factor here is the various connectors used, sourcing new C203 and C500 connectors, as well as different ECU connectors for the 2.5 vs 2.8.

I have found that failures that I have had in the harness are generally at splices, or at the pins themselves. For example, my C203 pins that powered the ECU were pretty corroded, and those are inside the cabin. Also I had a failure with the 2 wire harness that goes between the ignition control module and the ignition coil in the 2.8, that was easy to rebuild as you can buy both connectors with wire leads from Rockauto and crimp or solder them together. Fierostore sells them too.

I think in general it is worthwhile at some point to pull all the tape and tubing off the harness, inspect the splices and maybe re-do them, as well as check all the pins in the connectors for corrosion and replace them if necessary, I made a new post in tech recently outlining the engine harness connectors and the pins used in them at all the spots, along with wire color and wire gauge. Pins can be ordered for Mouser for less than a buck each, wire can be ordered from "The Wire Barn", go for GXL wire, and you can de-pin and reuse your stock connectors. I have these Wirefy Crimpers plus the open barrel crimp jaws that work with the GM crimps






All in all very low cost, and maybe a weekend worth of work and you can build a brand new harness with very little effort. Can be done in your living room while watching TV. You will want some depinning tools or a selection of picks to release the original pins for the connectors.

[This message has been edited by zkhennings (edited 02-15-2023).]

stevep914 FEB 15, 05:45 PM
I have identified the replacement connector as one for the AC. I will test tomorrow what burnt wires from the old connector do ( ground, power, signal, etc) and then splice in the new connector. I will try to fire the car with that hooked up, but suspect that connector and relay has no effect on running the car; just to power the two cooling fans in the engine compartment. If nothing changes except the fans run again, when I turn on the ignition ( as they used to before the connector burned, ) I will have to look elsewhere for my problem. I replaced the ICM a month or so ago, and went through a bad new one before getting one that worked ( Autozone crap, my only option here in Mexico)
stevep914 FEB 16, 03:09 PM
I am going to keep asking for input as I describe symptoms as I progress… today I wired in the new connector to the A/C relay, that used to power my two engine compartment cooling fans. With a tester, I have no power on any of the wires going into that, from the harnesses in the car. With no AC in the car anyway, I am assuming all this circuit used to do is run the cooling fans, and that circuit is now redundant. I can rewire the fans from some other source. I am assuming this has nothing to do with my problem starting the car. When I turn the ignition on, I have power to almost everything; windows front cooling fan, lights etc. when I try to engage the starter, there is a click, and then ALL power goes off for the car. Let it sit for a minute or two, and I have power again.. The battery reads 12.6 volts. I got under the car and tested the main power to the starter- good. When I ran a screw driver across to the solenoid terminal, I got a spark, a minimal result out of the starter, and then nothing. AND all power is off again for the whole car. Would I be wrong assuming there is a short in the starter solenoid? This may not be why the engine quit, while driving, but I am going through the steps here, and can’t see if the engine will fire until I get a working starter. Not sure why, after each time I try to engage the starter , I lose all power, and then after a couple of minutes, it comes back on by itself. What is that about? Thankyou for all your suggestions, Steve
Patrick FEB 16, 03:26 PM

quote
Originally posted by stevep914:

when I try to engage the starter, there is a click, and then ALL power goes off for the car. Let it sit for a minute or two, and I have power again.



What is the voltage reading at the battery junction terminal below the C500 connector immediately after "ALL power goes off for the car".
stevep914 FEB 16, 05:29 PM
Patrick, I will have to try that another day; been at this most of today and am beat. Where would I put the two probes from the multimeter to check this? I did pull out the starter and bench test it. It functions perfectly. Steve
Patrick FEB 16, 05:58 PM

quote
Originally posted by stevep914:

Where would I put the two probes from the multimeter to check this?



Put the positive lead on the battery junction terminal (which I pointed out to you Here), and the negative lead goes to ground (engine block).
stevep914 FEB 18, 02:00 PM
Thanks, Patrick, work is gonna be demanding for the next couple of days. Looking at the junction, it looks like it hasn’t been cleaned since the car was built, along with some of my other connections. I am going to try to clean everything along the path before I do any power checks. First, I have to reinstall the starter; I remember that not being fun trying to line up the holes for the bolts with the shim. I will update this after getting that done.
stevep914 FEB 20, 04:36 PM
Patrick, I cleaned both the terminal posts on the connection you have indicated, and their corresponding connection wires. Before trying to engage the starter, with power through the ignition ( all dash lights on) the voltage at the terminal is 11.34 volts. After trying to engage the starter ( which immediately cuts all power off) the reading is still 11.34 volts. I don’t know what that is telling me, except there is still power to that terminal even though the power appears to be off everywhere else ( no dash lights, power windows don’t work, etc. ) The fact that power cuts off immediately after the starter is tried, would indicate a short somewhere in the starter circuit? I have not gone after all the ground straps yet in the engine compartment. Steve
ArthurPeale FEB 20, 04:49 PM

quote
Originally posted by stevep914:

Patrick, I cleaned both the terminal posts on the connection you have indicated, and their corresponding connection wires. Before trying to engage the starter, with power through the ignition ( all dash lights on) the voltage at the terminal is 11.34 volts. After trying to engage the starter ( which immediately cuts all power off) the reading is still 11.34 volts. I don’t know what that is telling me, except there is still power to that terminal even though the power appears to be off everywhere else ( no dash lights, power windows don’t work, etc. ) The fact that power cuts off immediately after the starter is tried, would indicate a short somewhere in the starter circuit? I have not gone after all the ground straps yet in the engine compartment. Steve



Probably less a short, and more a really shitty connection on the battery terminal, or branching from it